JP2003072533A - Uphill start auxiliary device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To travel at a low speed by half-clutch operation even when started with the usage of an uphill start auxiliary device and enlarge freedom degree for changing release point setting by eliminating offset between a holding start point and a release point of a brake pressure set in correspondence with a stroke of a clutch pedal. SOLUTION: When traveling at the low speed by performing the half-clutch operation without removing a foot from the clutch pedal after the brake pressure is once held and the brake pressure is released by operation of the clutch pedal, the brake pressure is not immediately held even when the stroke of the clutch pedal reaches the brake pressure holding start point and the brake pressure is held after delay time (t) passes.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used in a vehicle equipped with a clutch pedal. According to the present invention, when the vehicle starts from a state in which the vehicle is stopped on a slope, the brake is automatically held even if the driver releases his / her foot from the brake pedal, and the clutch pedal is released beyond a preset release point. The present invention relates to an improvement of a slope start assist device that automatically releases a brake when the vehicle starts. TECHNICAL FIELD The present invention relates to an improvement for smoothly performing an operation of running a vehicle at a slow speed while maintaining a clutch pedal in a half-clutch state with a left foot and stepping on a brake pedal or an accelerator pedal with a right foot.

[0002]

2. Description of the Related Art When a vehicle stopped on a slope road is started in the direction of climbing the slope, the driver once performs a braking operation to apply a braking force to the vehicle, depresses the clutch pedal, and sets the transmission gear to the start gear. Then, loosen the brake while shortening the stroke of the clutch pedal.
Depress the accelerator pedal to increase the engine output. Such an operation is a basic procedure for driving an automobile having a clutch / pedal as a hill start operation. For large vehicles such as trucks and buses,
Depending on the size of the cargo and the number of passengers, the amount of operation varies greatly, and it is easy for the engine to stop or the vehicle to retreat when starting on a slope. As a device for assisting such driving operation, a slope start assist device has come to be widely used (Japanese Patent Laid-Open No. 60-11719 and Japanese Patent Laid-Open No. 4-24).
4462 publication).

In such a device, if the clutch pedal is deeply depressed when the vehicle speed becomes zero while the brake pressure exceeds a certain value by the operation of the brake pedal, the driver brakes. -It is configured to automatically maintain the brake pressure even when you release your foot from the pedal. In this state, if the transmission is engaged in the starting gear, the clutch pedal is removed, and when the stroke of the clutch pedal reaches the preset release point, the brake pressure held is automatically released. Controlled to be released. By using this device, the driver does not have to use nerves to control the stroke of the clutch with the left foot or the timing for quickly changing the right foot from the brake pedal to the accelerator pedal. become. Such a slope start assist device has come to be widely installed in lorries and the like. This device is used not only when starting uphill on a slope, but also when traffic is congested and when starting and stopping are repeated, to simplify the procedure of driving operation. It was

Here, in order to start the operation for maintaining the brake pressure even when the foot is released from the brake pedal as described above, the clutch pedal should be depressed at least to the release point of the brake pressure. is necessary. Then, in order to start the operation in which the brake pressure is maintained, a device has been proposed in which the stroke of the clutch / pedal must be stepped deeper than the release point of the brake pressure (Japanese Patent Application Laid-Open No. 1-1999). 604
55, Japanese Patent No. 2718037). That is, an offset is provided between the brake pressure holding start point and the brake pressure release point, rather than being set at the same point of the stroke of the clutch pedal. See FIG.
FIG. 3 will be described in more detail later.

In this device, when the brake pressure is automatically maintained, the clutch does not become a half-clutch state, that is, the braking force generated by maintaining the brake pressure is reduced by the half-clutch state. It is an excellent device that can prevent In addition, by providing this offset, in the case of low speed traveling on a congested road, garage entry operation of the vehicle, change of stop position, etc.
Only when the stroke of the clutch pedal is within the range of this offset, there is an advantage that traveling with a half clutch is possible without holding the brake pressure.

On the other hand, the slope start assist device is designed to allow the driver to adjust the release point position of the brake pressure by operation (Japanese Patent Laid-Open No. 8-119).
No. 080). This allows the driver to adjust and set the release point itself at which the brake pressure is released, to the side where the stroke of the clutch pedal is deep or to the side where the stroke is shallow. This allows
The driver can change the release point of the brake pressure depending on the road surface condition, the load condition, the mechanical wear of the clutch plate, or the driver's preference. A device that can change this release point by operation is very popular among users.

[0007]

By the way, a technique of providing an offset in the stroke of the clutch pedal between the above-mentioned start point of holding the brake pressure and the release point of the brake pressure, and the above-mentioned brake pressure With the technology that the driver can adjust the release point position of
Do not harmonize with each other. The driver adjusts the release point position of the brake pressure to the side with the larger stroke of the clutch pedal,
When the offset becomes zero, the above-described slow speed running operation cannot be performed. That is, if the vehicle is started using the slope start assist device and the vehicle is started at a slow speed while the clutch is disengaged in a half-clutch state after the vehicle starts, the stroke of the clutch pedal reaches the brake pressure holding start point. If the brake pedal is operated at this time, the brake pressure will be maintained. Such a situation often occurs in a situation in which a hill start assist device is used on a congested road to repeatedly stop and start.

Further, when it is attempted to adjust the release point position of the brake pressure to the side where the stroke of the clutch pedal is increased beyond the position where the offset becomes zero, the operation itself for holding the brake pressure acts. Disappear. In this case, the slope start assist device cannot be used effectively.

When the driver changes the release point position of the brake pressure, the value of the offset is maintained as it is, and the holding start point position of the brake pressure is changed together with the change of the release point position. It is conceivable to configure the software of the control circuit, but in this case, it is physically impossible to configure the brake pressure holding start position to move deeper than the deepest position of the clutch pedal stroke. . Therefore, the range in which the release point position can be changed is narrowed by the offset, and the advantage that the release point position can be changed is substantially eliminated. In other words, between the brake pressure release point and the brake pressure holding start point, the clutch
Even if the brake pressure release point position can be changed by the operation by providing an offset to the pedal stroke, the clutch is released from the state where the brake pressure release point is connected to the clutch. It becomes impossible to change over a wide range up to the state.

The present invention has been made against such a background, and an offset is not provided for the stroke of the clutch pedal between the brake pressure holding start point and the brake pressure release point. SUMMARY OF THE INVENTION It is an object of the present invention to provide a hill start assisting device capable of running a vehicle at a slow speed in a half clutch state. SUMMARY OF THE INVENTION An object of the present invention is to provide a slope starting assistance device capable of changing a brake pressure release point in a wide range by a driver's operation.

[0011]

Means for Solving the Problems When the vehicle is started at a slow speed while maintaining a half-clutch state after the vehicle is started using the slope starting assist device, the driver makes the stroke of the clutch pedal shallow. Operate (small) to continue clutch operation without releasing the foot from the clutch pedal even after passing the brake pressure release point. The present invention focuses on such a habit of driving operation, and after the stroke of the clutch pedal reaches the release point of the brake pressure, the clutch pedal is not once released and the half-clutch operation is continued. If the stroke of the clutch pedal is operated again to the starting point for holding the brake pressure and the brake pedal is stepped on, the holding of the brake pressure is started after the passage of the holding start point is detected. The greatest feature is that a delay time (t) is provided before.

That is, according to the present invention, a brake pressure generating means (15, 16, 17) associated with a brake pedal is provided.
A solenoid valve (9) provided in a passage for supplying the brake pressure to the brake cylinder for holding and releasing the brake pressure of the brake cylinder, a vehicle speed sensor (1),
A clutch stroke sensor (2), a control circuit (10) for supplying a control current to the solenoid valve (9) by using an output of a gear switch (5) as an input, and the control circuit (10) is a brake circuit. When the pedal (11) is depressed and the vehicle is stopped, the brake pedal is released while the clutch pedal is depressed with a stroke larger than the starting point of holding the brake pressure. The means for holding the brake pressure and the brake pressure held by the means when the transmission is in the starting position with the brake pressure held and the stroke of the clutch / pedal becomes smaller than the release point of the brake pressure. In a slope start assist device including means for releasing,

The control circuit (10) once holds the brake pressure and then releases the clutch pressure.
When the brake pedal is stepped on while the clutch pedal is stepped over the holding start point without the pedal stroke returning to zero, the stroke of the clutch pedal becomes the holding start point. It is characterized in that a delay time (t) is provided before the brake pressure is maintained.

The numbers in the above parentheses are the reference numbers in the drawings of the embodiment apparatus which will be described later. This is given for easy understanding of the structure of the invention, and is not for understanding the structure of the invention by limiting it to the embodiments.

With such a configuration, the holding start point and the release point are set at points at which the strokes of the clutch pedal are substantially equal, and it is not necessary to provide the offset described above, and the slope start assist device can be provided. After using the vehicle to start the vehicle, it is possible to perform a slow-speed running operation such as entering the garage or changing the stop position in the half-clutch state. And
Since the offset is eliminated, the range in which the driver can change the release point of the brake pressure by operation becomes large.

When the stroke of the clutch pedal is zero,
It is when the state where the foot is released from the clutch pedal is detected, but as a practical structure, it can be when the stroke of the clutch pedal reaches a detection point set near zero. .

The above-mentioned delay time (t) is a time for executing a single slow speed running, and it is suitable to be several seconds to several tens of seconds. More specifically, it is appropriate that the delay time (t) is selectively set between 5 seconds and 30 seconds. Before the delay time (t) elapses, if the stroke of the clutch pedal is operated again in the direction in which the stroke becomes smaller and the holding start point is passed again, the delay time is passed when the holding start point is passed again. It is desirable that the timing of (t) be reset and the timing be restarted from time zero.

In the control circuit of the present invention, when the release point of the brake pressure is changed by an operation, the starting point of holding the brake pressure is automatically changed at the same time so as to be changed at the same time.
It is desirable to configure the software. With this arrangement, the offset described above is always maintained at zero or a very small value.

[0019]

1 is a block diagram of an apparatus according to an embodiment of the present invention. This device includes a vehicle speed sensor 1, a clutch stroke sensor 2, a service brake switch 3 that detects the operating state of a service brake, a parking brake switch 4 that detects the operating state of a parking brake, and a gear that detects the state of a transmission. A control circuit 10 having each output electric signal of the switch 5 as input information is provided.
The control circuit 10 is a program control circuit. The arithmetic control output of the control circuit 10 is supplied to the solenoid valve 9 that drives the brake valve 12 and the alarm device 14.

Explaining the brake system, the pneumatic tank 1
From 5, the air pressure is supplied to the brake valve 12 via the rear brake valve 16 and the front brake valve 17, which are opened and closed according to the operation of the brake pedal 11. The air pressure controlled by the brake valve 12 is supplied to the rear brake booster 18 and the front brake booster 19. When a control signal is sent to the solenoid valve 9 while air pressure is being sent to the rear brake booster 18 and the front brake booster 19, the brake pressure is maintained even if the brake pedal 11 is released, and the solenoid valve is released. When the control signal of 9 disappears, the brake pressure is released. The operation unit 13 is provided in the driver's seat and its operation switch 1
When the 3a is operated in the on state, the slope start assisting device is in an effective state. The operation switch 13a is in the off state when the hill start assist device is not required. The operation unit 13 is also provided with a release point position adjusting end 13b.
By operating, the release point of the brake pressure can be operated and set in the direction in which the stroke of the clutch pedal is deep or in the direction in which the stroke is shallow. Further, when the driving operation or the operation of the device is improper and the device cannot follow the operation or the device has a failure, the alarm buzzer 14a is provided.
Alternatively, an alarm is issued by the alarm lamp 14b.

The feature of the present invention lies in the operation of the control circuit 10. FIG. 2 is a main part flowchart showing the operation of the device control circuit according to the embodiment of the present invention. When the vehicle speed is zero, the parking brake is released, the transmission is engaged in the starting gear (forward or reverse), the service
The control circuit 10 sends a control signal to the solenoid valve 9 when the clutch pedal is operated in the direction in which the stroke is increased while the brake pedal of the brake is depressed and the release point is exceeded. As a result, the solenoid valve 9 maintains the brake pressure of the brake cylinder, and the brake pressure is maintained even if the driver releases his / her foot from the brake pedal 11.

At this time, the apparatus of the present invention discriminates whether or not there is a history (history) in which the stroke of the clutch pedal is returned to the set stroke zero after the previous release of the brake pressure. When this has been returned,
As described above, the solenoid valve 9 is controlled to execute the operation for holding the brake pressure.
Timing of the delay time (t) is started. During this timing, holding operation of the brake pressure is suspended, and after this time has elapsed the set delay time (t), if the vehicle speed is zero, the parking flex is released, and the brake pedal is depressed at gear-in, the brake is applied. Perform an action to hold the pressure. The operation of releasing the brake pressure is the same as that of the conventional device.

By performing such control, the vehicle can be driven at a very low speed while the half-clutch operation is continued after the vehicle has started using the slope start assist device.
This is often the case on busy roads. In addition, when changing the stop position of the vehicle or entering the garage, the vehicle will not release the clutch pedal even after the vehicle has started, and the vehicle will move forward or backward at a very low speed while adjusting the clutch pedal to the half-clutch state. I do. At this time, even if the clutch pedal reaches the brake pressure holding start point again, since the clutch pedal has not been returned to the stroke zero once, the delay time measurement starts, but the brake pressure holding state immediately changes. I won't.

The delay time (t) is suitably set to a few seconds to a few tens of seconds as described above, but in this embodiment, it was set to 10 seconds as an example. Therefore, the brake pressure is not retained even if the brake pedal is depressed for 10 seconds. If the stroke of the clutch pedal is manipulated during this low speed running, and the brake pressure holding start point may be passed again, the timing of the delay time (t) is reset here and the timing is restarted. It If the delay time (t) elapses after the stroke of the clutch pedal has passed through the brake pressure holding start point and becomes large, and then the vehicle speed is zero, the parking brake is released, and the brake pedal is depressed due to gear-in, , Its brake pressure is automatically maintained.

FIG. 3 is a diagram for explaining the holding start point and the release point of the brake pressure with respect to the stroke of the clutch pedal. When the stroke (St) of the clutch pedal is plotted on the horizontal axis and the clutch hydraulic pressure is plotted on the vertical axis, the clutch pedal is deeply depressed from the released state, and when the clutch pedal is operated again to the released state, the clutch hydraulic pressure is indicated by an arrow in FIG. It becomes a locus like a curve attached. With the configuration of the present invention, the holding start point and the release point can be set to the same point with respect to the stroke of the clutch pedal, as shown in FIG. FIG. 3B shows a case where an offset is provided between the holding start point and the release point of the brake pressure (conventional device). If this offset section is made large to some extent, it is possible to use the half-clutch state in this offset section to perform operation at a slow speed, but even if the brake pressure release point is changed by operation, the clutch・ The degree of freedom to change the pedal stroke to the larger side will be limited.

When it is necessary to drive at a slow speed when the vehicle is in a loading / unloading place or a parking lot, the operation switch 13a of the operation unit provided in the driver's seat is operated to move on a slope. By starting the vehicle after stopping the operation of the starting auxiliary device, the brake pressure is never held at an unintended timing due to the half-clutch operation. Further, when the engine key switch is turned off and the engine is stopped, the electric power supplied to the slope start assist device is cut off.
Even if the engine key switch is turned on again, the slope start assisting device is configured to stop its function until the operation unit 13 is operated. Therefore, even when the engine is started by the engine key switch and then the vehicle runs at a low speed immediately, the function of the present invention does not operate, and the brake pressure is not held at an unintended timing.

[0027]

According to the present invention, the vehicle is allowed to run at a slight speed in the half-clutch state without providing an offset with respect to the stroke of the clutch pedal between the brake pressure holding start point and the brake pressure release point. It is possible to provide a slope starting assistance device capable of In the device of the present invention, the half-clutch operation can be performed in a wider range than when the offset described above is set.
Further, according to the present invention, the release point of the brake pressure can be changed over a wide range according to the driver's operation.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of an apparatus according to an embodiment of the present invention.

FIG. 2 is a flowchart for explaining the operation of the main part of the control circuit of the device of the embodiment of the present invention.

FIG. 3 is a diagram illustrating a stroke of a clutch pedal.
(A) is the case of the device of the present invention (b) is the case where an offset is provided (comparative example)

[Explanation of symbols]

1 vehicle speed sensor 2 Clutch stroke sensor 3 Service brake switch 4 Parking brake switch 5 gear switch 9 Solenoid valve 10 Control circuit 11 Brake pedal 12 Brake valves 13 Operation unit 13a Operation switch 13b Adjustment end of brake pressure release point 14 Alarm device 14a Alarm buzzer 14b alarm lamp 15 Pneumatic tank 16 Rear brake valve 17 Front brake valve 18 Rear brake booster 19 Front brake booster

Claims (2)

[Claims] 1. A brake pressure generating means associated with a brake pedal, an electromagnetic valve provided in a passage for supplying the brake pressure to the brake cylinder, for holding and releasing the brake pressure of the brake cylinder, a vehicle speed sensor, A control circuit for supplying a control current to the solenoid valve by using an output of a clutch stroke sensor and a gear switch as an input, and the control circuit includes a clutch circuit when a brake pedal is depressed and the vehicle is stopped. The brake pedal is released when the pedal is stepped on a stroke larger than the brake pressure holding start point. When the driving operation is performed, a means for holding the brake pressure, and a shift operation while the brake pressure is held The machine is in the starting position and the stroke of the clutch pedal is smaller than the release point of the brake pressure. And a means for releasing the brake pressure held by the means, in the slope start assist device, the control circuit, after performing an operation of holding and releasing the brake pressure, once the stroke of the clutch pedal is zero. If the brake pedal is stepped on beyond the holding start point and the brake pedal is stepped on again until the brake pressure is held after the clutch pedal stroke reaches the holding start point. A hill start assist device characterized by having a delay time. 2. The slope start assisting device according to claim 1, wherein the holding start is set at a point where the holding start point and the release point are substantially equal to the stroke of the clutch pedal.