JP2006137340A - Brake control system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a brake control system capable of realizing reduction of fatigue by assisting a driver's brake operation. <P>SOLUTION: Stepping action of a brake pedal 1 is detected by a control circuit 14 at low speed traveling and when a vehicle speed become zero, energization is performed on a solenoid energization closure valve type solenoid valve 6 to close a piping passage continued on a wheel brake cylinder 3 and braking force immediately before is retained. Thereafter, energization of the solenoid valve 6 is stopped when an acceleration pedal 10 is stepped and it is returned to the usual brake state. The brake is not relaxed at stopping even if the leg is left from the brake pedal 1 and since operation of the acceleration pedal 10 is always required for movement of the vehicle, the movement of the vehicle not intended by a driver can be prevented. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a vehicle brake system, and more particularly to a vehicle brake control system including an accelerator pedal and a brake pedal.

  For vehicles with accelerator and brake pedals, such as MS (manual) vehicles including buses and trucks, AT (automatic) vehicles, motorcycles and motor vehicles with special vehicles such as tractors, the driver of these pedals Proper operation is an essential element for ensuring safety.

  Therefore, various devices have been proposed in order to support (back up) the brake operation of the driver. One type of the device is ABS (anti-lock brake system), which is widely used as an effective means for ensuring safety. (For example, see Non-Patent Document 1).

  As is well known, the ABS controls the braking force so that the wheels (wheels, tires) are not locked while the vehicle is running when the brake is operated, thereby suppressing sliding (skid) and stabilizing the running direction. The control at this time is so-called pumping brake control.

  By the way, in recent years, the traffic volume has continued to increase, and the occurrence of traffic congestion has been increasing due to road conditions, but at the time of this traffic congestion, repeated operation of stopping and slow forward is required.

And in this case, if the distance between the front car and the host vehicle is widened, release the brake pedal and depress the accelerator pedal to move forward at a slow speed. Although it is necessary to repeat, at this time, the conventional vehicle depends entirely on the brake operation and the accelerator operation by the driver.
July 1996, All-Japan Lotus Doyukai, published by Lotus Corporation, “Lotus Fault Diagnosis Manual [A / T Mission Chassis]”

  The above prior art does not give consideration to the feeling of suppression (pressure) that the driver receives both physically and mentally as the brake pedal is continuously depressed, and has a problem in ensuring safe driving.

  As described above, repeated operation of stopping and slow forward is required when there is a traffic jam.In this state, for example, in the case of an AT vehicle, if the transmission select lever remains in the drive position, the vehicle creeps (creep) Therefore, in the prior art, the brake pedal must be continuously depressed even when stopped.

  At this time, in order to keep the vehicle stopped, in addition to continuing to depress the brake pedal, the shift lever of the transmission may be set to the parking position or the side brake may be operated. The operation to continue is simpler and more realistic.

  However, in this case, every time you stop, you will continue to step on the brake pedal.As a result, fatigue of the legs will increase as the stop time elapses, and the physical condition of the driver will deteriorate both physically and mentally. There is a risk of unintentionally removing the foot from the brake pedal. In this case, the vehicle moves forward and a danger of collision occurs. Therefore, in the prior art, a problem arises in ensuring safe driving.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a brake control system that can assist a driver's brake operation to reduce fatigue.

  In the vehicle brake control system including an accelerator operation means and a brake operation means, the above object is provided with a brake force holding means for holding a brake force immediately before stopping when traveling is stopped by the brake operation means, The braking force held by the braking force holding means is achieved so as to be released when the accelerator operating means is operated.

  Therefore, the present invention is characterized in that when the brake is stepped on once during low speed traveling in a traffic jam, the appropriate braking force immediately before the stop is maintained, and when the accelerator is depressed, the holding of the braking force is automatically released. To do.

  At this time, even if the holding operation of the braking force by the braking force holding means is made effective only when the traveling speed of the automobile is 10 Km / hr or less, the above object is achieved, and further, the braking force holding means The braking force holding operation is validated when the maximum depression movement amount with respect to the brake operating means is M, and the depression movement amount M1 in the relationship of M ≧ M2> M1, and is invalidated when the depression movement amount is M2. Even if it does so, the said objective is achieved.

  Further, at this time, when the travel of the vehicle is stopped by the brake operation means, means for switching the automatic transmission to the neutral position is provided, and the accelerator operation means is operated at the neutral position of the automatic transmission. It may be released at times.

  According to the present invention, after the vehicle is stopped by depressing the brake pedal, the brake force immediately before the stop is maintained even if the brake pedal is released unless the accelerator pedal is touched. In contrast, the vehicle can be prevented from moving.

  Therefore, according to the present invention, it is not necessary to keep stepping on the brake pedal when the vehicle is stopped, so that the fatigue of the driver's mind and body that appears when the pedal is continuously depressed is greatly reduced. can do.

  In particular, the foot can be removed from the brake pedal when there is a traffic jam or when waiting for a long signal, which is effective in reducing the burden on the driver.

  Hereinafter, a brake control system according to the present invention will be described in detail with reference to embodiments shown in the drawings.

  FIG. 1 and FIG. 2 show an embodiment in which the present invention is applied to a vehicle (AT car) equipped with an ABS and equipped with an automatic transmission. Accordingly, in this case, the basic operation as a normal brake is as shown in the normal brake mode of FIG.

  That is, the brake master cylinder 2 operated by the brake pedal 1 is provided, and when the brake pedal 1 is depressed, the brake fluid pressurized by the brake master cylinder 2 acts on the wheel brake cylinder 3, and the brake disc rotor 4 Is pressed and the brake is applied.

  In this embodiment, as shown in the figure, the brake system is provided with a booster (bacium booster) known by a trade name such as a master bag, but the present invention does not have a booster. Needless to say, it can also be applied to a brake system.

  In this embodiment, among the solenoid valves provided in the ABS unit 5, for example, a solenoid energization valve type solenoid valve 6 called a holding solenoid valve is used, and this is controlled by the control circuit 14. The brake fluid circuit is operated by switching between the normal brake mode shown in FIG. 1 and the brake holding mode shown in FIG.

  Therefore, first, the first brake switch 8 and the second brake switch 9 are arranged on the brake pedal 1, and then the accelerator switch 11 is arranged on the accelerator pedal 10. Further, a vehicle speed sensor 12 is provided on the wheel. Then, signals from these are input to the control circuit 14.

  On the other hand, a display lamp 13 and an activation switch 15 are connected to the control circuit 14, and a shift selection solenoid valve group 17 that determines the operating position of the automatic transmission 16 is also connected to the control circuit 14.

  First, the first brake switch 8 is turned on (the contact is closed) when the brake pedal 1 is lightly depressed, and then the second brake switch 9 is turned on when the brake pedal 1 is strongly depressed. It is installed in the vicinity of the brake pedal 1.

  At this time, specifically, when the maximum depression amount (stroke) of the brake pedal 1 is M, the depression amount when the first brake switch 8 is turned on is M1, and when the second brake switch 9 is turned on When the amount of stepping movement is set to M2, the installation is performed such that M ≧ M2> M1.

  Accordingly, the types of these switches 8 and 9 are normally open contact (NO: normally open) type switches. At this time, for example, it is convenient to use a microswitch, but magnetism or light is used. A contactless switch may be used.

  Next, the accelerator switch 11 is installed in the vicinity of the accelerator pedal 10 so as to be turned on when the accelerator pedal 10 is depressed. Therefore, the accelerator switch 11 is also a normally open contact type, and a micro switch or a non-contact switch may be used as well.

  The accelerator switch 11 is turned on immediately after the accelerator pedal 10 is depressed. However, it is desirable that the accelerator switch 11 is not switched on depending on other factors such as vehicle vibration unless the accelerator pedal 10 is depressed.

  The vehicle speed sensor 12 detects the rotation of the wheel as a pulse signal so that the vehicle speed can be calculated by the control circuit 14, and an electromagnetic pickup type pulse sensor is usually used.

  As shown in the figure, the control circuit 14 receives signals from the first and second brake switches 8 and 9, the accelerator switch 11 and the vehicle speed sensor 12, and executes a predetermined calculation process based on them. The opening and closing of the electromagnetic valve 6 is controlled, and the lighting of the display lamp 13 is controlled. At this time, the activation switch 15 functions to enable control by the control circuit 14 only when it is turned on.

  Next, as described above, in this embodiment, the present invention is applied to a vehicle equipped with an automatic transmission, that is, a so-called AT vehicle, and thus includes an automatic transmission 16 and a shift selection electromagnetic valve group 17. ing.

  Therefore, the control circuit 14 also controls the shift selection electromagnetic valve group 17. At this time, as is well known, in the case of an AT vehicle, the shift selection electromagnetic valve group 17 is used to select the automatic transmission. It is customary to be controlled by the position of the lever.

  However, in this embodiment, only when the select lever is in the D (drive) position, the N (neutral) position selection solenoid valve 18 and the D position selection solenoid valve 19 in the shift selection solenoid valve group 17 are connected to the control circuit 14. Thus, the control can be performed with priority over the control by the position of the select lever.

  Next, the operation of this embodiment will be described with reference to the flowchart of FIG. 3 is executed by the control circuit 14. At this time, the control by the control circuit 14 is executed by one of the programs stored in the ABS control computer. It is something that has come to be.

  First, the processing according to the flowchart of FIG. 3 is performed when the system is activated, that is, after the key is inserted into the key switch on the operation panel of the vehicle and operated to the accessory position, and the activation switch 15 is turned on. Be started when

  At this time, as already explained, the solenoid valve 6 is a solenoid energized closed type, and the valve remains open when not energized. Therefore, the operation mode of the system at this time is the normal brake mode shown in FIG. 1 and functions as a normal brake system.

  This state is ensured by executing initial processing (initialization) when processing is started, so that the operation as an original brake system is guaranteed and safety is reliably maintained. ing.

  When the processing is started and the initial processing is executed, the vehicle speed V is first taken in (processing step S1). That is, the rotational speed (rotational speed) of the wheel is measured from the cycle of pulses supplied from the vehicle speed sensor 12, and the vehicle speed V is calculated.

  Next, the vehicle speed V just calculated is compared with a predetermined determination value set in advance, for example, a determination value of 10 km / hr, and it is checked whether or not the vehicle speed V is equal to or lower than the determination value (processing step S2). When the result is N (negative), that is, when the vehicle speed exceeds 10 km / hr, the processing is terminated here.

  The determination value at this time is a so-called threshold value, but this is not limited to 10 km / hr, and may be set to an arbitrary value within a range of 5 to 10 km / hr, for example, as necessary. .

  On the other hand, when the determination result in this processing step S2 is Y (positive), that is, when the vehicle speed V is a low speed of 10 km / hr or less, it is checked whether or not the first brake switch 8 is on (processing step S3). . If the result is N, that is, if the first brake switch 8 is OFF (the contact is open), the process is terminated here.

  On the other hand, when the determination result in this process step S3 is Y, that is, when the first brake switch 8 is on, it is further checked whether or not the second brake switch 9 is off (processing step S4). When the result is N, that is, when the second brake switch 9 is turned on this time, the processing is ended here.

  On the other hand, if the determination result in processing step S4 is Y, that is, if the second brake switch 9 is OFF, the vehicle speed V is taken in again (processing step S5), and then whether the vehicle speed V is 0 km / hr this time. Whether or not it is stopped is checked (processing step S6). Then, when the result is N, that is, when the vehicle speed V is not 0 km / hr, the process ends here.

  On the other hand, when it is determined that the determination result in this processing step S6 is Y, that is, the vehicle speed V is 0 Km / hr, the solenoid valve 6 and the display lamp 13 are energized (processing step S7). .

  Then, the valve of the electromagnetic valve 6 is closed. As a result, the brake holding mode shown in FIG. 2 is shifted here, and the display lamp 13 is lit. At this time, the processing step S10 is also executed in parallel, which will be described later.

  Here, the brake holding mode of FIG. 2 will be described. In this mode, when the solenoid valve 6 is closed, the pipe line leading to the wheel brake cylinder 3 is cut off from the pipe line leading to the brake master cylinder 2, The pipe line of the wheel brake cylinder 3 is closed.

  By the way, the condition for shifting to the brake holding mode shown in FIG. 2 is that the step S3 and the step S6 are present in the flowchart of FIG. And the vehicle speed V is 0 km / hr, that is, it is assumed that the vehicle has stopped.

  Then, immediately before shifting to the brake holding mode shown in FIG. 2, a braking force corresponding to the force applied to the brake pedal 1 at this time is working.

  Therefore, when the mode is shifted to the brake holding mode in FIG. 2, the brake force that was applied immediately before is held as it is. Then, because this is called the brake holding mode, as a result, even if the driver removes his / her foot from the brake pedal 1, the vehicle remains braked, and therefore there is no possibility that the vehicle starts to move.

  At this time, since the display lamp 13 is lit, the driver is notified that the brake holding mode has been entered, so that the driver can safely lift his / her foot from the brake pedal 1.

  When the processing step S7 is executed in this way and the mode shifts to the brake holding mode shown in FIG. 2, the process proceeds to the processing step S8, where it waits for the accelerator switch 11 to be turned on. That is, the signal input from the accelerator switch 11 is monitored to check whether or not it is turned on. The signal is returned to the original state during the off state, and when it is turned on, the process proceeds to the next processing step S9.

  In process step S9, the energization to the solenoid valve 6 and the display lamp 13 is stopped. Note that the processing step S11 is also executed in parallel at this time, which will be described later.

  Then, since the solenoid valve 6 is first restored and the closed valve is opened, the system returns to the normal brake mode of FIG. 1, and the display lamp 13 is turned off to notify that the brake holding mode has been canceled. Then, after executing this process step S9, the process returns to the first process step S1, and the same process is repeated again.

  Next, the content of assistance given to the driver's brake operation by the above processing according to this embodiment will be described.

  First, as shown in the flowchart of FIG. 3, since there are the processing steps S1 and S2, the normal brake mode of FIG. 1 is maintained even when the vehicle is running, as long as the vehicle speed does not become 10 km / hr or less.

  Therefore, until you are forced to drive at a low speed by getting involved in a traffic jam or entering a zone where traffic signals are restricted by traffic signals, you may feel uncomfortable even if you brake during cruising. The acceleration and deceleration can be arbitrarily performed as necessary.

  On the other hand, if the vehicle starts traveling at low speed, the process proceeds to step S3, where the system is prepared for operation. However, even at this time, when the brake pedal 1 is strongly depressed, the preparation for the operation of the system is canceled by the processing step S4.

  Therefore, according to this embodiment, when the brake pedal 1 is strongly depressed, it is possible to suppress the shift to the brake holding mode, thereby eliminating the possibility of hindering the necessary brake control by the ABS. As a result, it can be easily applied to an ABS-equipped vehicle, and it can be expected to support brake control by ABS.

  Thereafter, on the condition that the vehicle speed is 0, that is, the vehicle is stopped, the brake holding mode of FIG. 2 is entered, and the braking force is held regardless of the depression state of the brake pedal 1, and this state is This is maintained until the accelerator pedal 10 is operated.

  In this brake holding mode, as described above, even if the driver removes his / her foot from the brake pedal 1, there is no fear that the vehicle will start moving while the brake is applied, and the display lamp 13 is lit at this time. Therefore, since it is notified that the vehicle is in the brake holding mode, the driver can lift his / her foot from the brake pedal 1 with peace of mind.

  Therefore, even when the vehicle enters a traffic jam or waits for a long signal, after the brake pedal 1 is depressed and the vehicle is temporarily stopped, the foot can be arbitrarily released from the brake pedal 1, so that the vehicle is stopped. Further, it is not necessary to continue to depress the brake pedal 1, and the driver's mental and physical fatigue can be greatly reduced, thereby contributing to maintenance of safe driving.

  In addition, the brake holding mode is automatically released just by depressing the accelerator pedal 10, and the brake is immediately released. Therefore, when the accelerator pedal 10 is depressed, the distance between the vehicles opens or the traffic signal changes. The vehicle can be started immediately, and as a result, it is easy to follow the previous vehicle and always keep a proper distance and respond quickly to traffic signal changes, responding to traffic jams and traffic signals Accurate operation can be performed.

  As described above, according to this embodiment, after the vehicle is stopped by depressing the brake pedal 1, the brake force immediately before the stop is maintained even if the foot is released from the brake pedal 1 as long as the accelerator pedal 10 is not touched. Therefore, it is possible to prevent the vehicle from moving against the will of the driver.

  Therefore, according to this embodiment, it is not necessary to keep stepping on the brake pedal 1 in order to maintain the vehicle stop state at the time of stop, so that the mental and physical fatigue when the pedal is continuously depressed is greatly reduced. be able to. At this time, since the foot can be removed from the brake pedal 1 particularly in a traffic jam or when waiting for a long signal, it is effective in reducing the burden on the driver.

  Further, according to the above-described embodiment, since the operation of the accelerator pedal 10 is necessarily required for the movement of the vehicle, the movement of the vehicle not intended by the driver is prevented, and as a result, when the vehicle stops on a hill or the like, it is not known. There is no risk of the vehicle moving forward or backward during this time, and accidents can be prevented.

  Here, the role of the activation switch 15 will be described. As described above, the switch 15 functions to enable the mode transition operation by the control circuit 14 only when it is turned on. Normally, it is desirable to leave it on.

  This is because if the vehicle is turned off, the vehicle may move forward due to the creep of the AT car when the brake pedal 1 is accidentally released when the vehicle is stopped. This is because there is no hindrance to driving.

  Here, even if it gets into a traffic jam, there are times when it is a non-noro drive instead of a stop and a run repeatedly. In this case, only the operation of the brake pedal is operated using the creeping of the AT car. There are cases in which it is easier to follow if you are traveling in a non-no-ro.

  Therefore, at this time, if the activation switch 15 is utilized and the switch is turned off, the mode shift operation by the control circuit 14 is prohibited. Therefore, the brake pedal can be easily operated by adjusting the brake pedal depression force. can do.

  By the way, in this embodiment, the processing step S10 and the processing step S11 are provided in the control processing by the control circuit 14 as shown in the flowchart of FIG. Therefore, hereinafter, the processing step S10 and the processing step S11 will be described.

  First, in process step S10, the energization of the D position selection solenoid valve 19 in the shift selection solenoid valve group 17 is turned off, and the energization of the N position selection solenoid valve 18 is turned on. Therefore, the control position of the automatic transmission 16 that has been in the D position until then is switched to the N position at this point.

  On the other hand, in the subsequent processing step S11, the energization of the N-position selection solenoid valve 18 is turned off, and the energization of the D-position selection solenoid valve 19 is turned back on. Therefore, this time, the control position of the automatic transmission 16 is switched from the N position to the D position.

  Accordingly, in this embodiment, when the brake holding mode is set, the control position of the automatic transmission 16 is also set to the N position in parallel with this, and as a result, the load applied to the engine in the brake holding mode is set. Can be lightened.

  This is because the load on the engine in the idle state is lighter when the control position of the automatic transmission 16 is at the N position than when it is at the D position. According to the embodiment, since the fuel consumption during idling can be suppressed, energy saving can be achieved, which can contribute to environmental measures.

  Further, as a result of reducing the load on the engine in this way, the residual torque by the automatic transmission 16 is eliminated, so that there is no fear of creep and further safety can be expected.

  As described above, according to the above-described embodiment, it is possible to eliminate the need to continue to step on the brake pedal 1 during a traffic jam or a stop while waiting for a signal, thereby reducing driver fatigue and contributing to safe driving. Can do.

  Moreover, according to the said embodiment, since a part of structure can be shared with the existing ABS system, a cost increase can be suppressed.

  In the above embodiment, the AT vehicle is targeted, but it goes without saying that the present invention is also applicable to a manual vehicle. This is because even in the case of a manual vehicle, the clutch is always disengaged or the gear is neutralized when the vehicle stops.

It is the block block diagram which showed one Embodiment of the brake control system by this invention in the state at the time of normal brake mode. It is the block block diagram which showed one Embodiment of the brake control system by this invention in the state at the time of brake holding mode. It is a flowchart for demonstrating operation | movement of one Embodiment of the brake control system by this invention.

Explanation of symbols

1: Brake pedal 2: Brake master cylinder 3: Wheel brake cylinder 4: Brake disc rotor 5: ABS (anti-lock brake system) unit 6: Solenoid valve (solenoid energized valve)
8: First brake switch 9: Second brake switch 10: Accelerator pedal 11: Accelerator switch 12: Vehicle speed sensor 13: Display lamp 14: Control circuit 15: Activation switch 16: Automatic transmission (AT)
17: Shift selection solenoid valve group 18: Neutral solenoid valve 19: Drive solenoid valve

Claims (4)

In a vehicle brake control system having an accelerator operation means and a brake operation means,
When the travel of the vehicle is stopped by the brake operation means, provided is a brake force holding means for holding the brake force immediately before the stop,
The brake control system for a vehicle, wherein the brake force held by the brake force holding means is released when the accelerator operation means is operated. The vehicle brake control system according to claim 1,
A brake control system for a vehicle, wherein the brake force holding operation by the brake force holding means is made effective only when the traveling speed of the automobile is 10 Km / hr or less. The vehicle brake control system according to claim 1,
The brake force holding operation by the brake force holding means is enabled when the maximum depression movement amount with respect to the brake operation means is M, and the depression movement amount M1 in the relationship of M ≧ M2> M1, and the depression movement amount is M2. A brake control system for a vehicle, which is disabled when The vehicle brake control system according to claim 1,
A means for switching the automatic transmission to a neutral position when the vehicle is stopped by the brake operation means;
The vehicle brake control system is characterized in that the neutral position of the automatic transmission is released when the accelerator operating means is operated.

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