JPH0585319A - Braking device for vehicle - Google Patents

Abstract

PURPOSE:To provide a braking device for vehicles which is capable of improving the durability of a stopping brake and allows a vehicle to travel without operating an accelerator pedal when the vehicle restarts after it is stopped, with an automatic transmission shifted to a drive range or a neutral range. CONSTITUTION:In a braking device for vehicles which has a parking brake 50 and brales 7FR-7RR and in which the brakes 7FR-7RR operate as a stopping brake 30 when the parking brake 50 is not operated and a vehicle is stopped, the stopping brake 30 is adapted not to be operated for a specified time immediately after the parking brake is released, and thereafter the stopping brake 30 is operated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle brake system, and more particularly to a vehicle brake system having a stop brake.

[0002]

2. Description of the Related Art Conventionally, a stop brake (also called a service brake or a hill holder mechanism) as described, for example, in Japanese Utility Model Laid-Open No. 61-41072, is used to ensure the safety of a vehicle at the time of stop. Brake devices for vehicles equipped with the same are known. This stop brake mechanically operates the foot brake when the vehicle is stopped and the parking brake is not operated.

In the vehicle brake device described in the above publication, when the parking brake is operated during the operation of the stop brake having the braking force holding function, the stop brake is released after a predetermined time has elapsed from the start of the operation of the parking brake. This reduces the operating force of the parking brake and prevents the vehicle from slipping backward.

[0004]

On the other hand, conventionally, in an automatic vehicle, when the vehicle restarts after being stopped, the function of the stop brake is favorably operated under various conditions and, for example, the automatic transmission is set to the D range or There is a need to run on a flat road or a slope without shifting the accelerator while shifting to the N range. A vehicle brake system that meets such needs has not yet been proposed.

Therefore, the present invention has been made to meet the above-mentioned needs, and improves the reliability of the stop brake and shifts the automatic transmission to the D range or the N range when the vehicle restarts after stopping. It is an object of the present invention to provide a vehicle brake device that can travel without performing an accelerator operation.

[0006]

In order to achieve the above object, the present invention has a parking brake and a brake, which operates as a stop brake when the parking brake is inactive and when the vehicle is stopped. A feature of the vehicle brake device is that the stop brake is deactivated for a predetermined time immediately after the parking brake is released, and then the stop brake is activated.

In the present invention thus constructed,
Since the stop brake is deactivated for a predetermined time immediately after releasing the parking brake, it is possible to travel on a flat road or a slope without accelerator operation, for example, with the automatic transmission shifted to the D range or the N range. Further, since the stop brake is activated after that, the reliability of the stop brake is also improved.

Further, in the present invention, when the vehicle speed is equal to or lower than the predetermined value and the brake pressure is equal to or higher than the predetermined value, it is determined that the vehicle is stopped. Therefore, it can be reliably determined whether or not the vehicle is stopped. Further, in the present invention, when the front wheel of the vehicle is the driving wheel and the rear wheel is the driven wheel, the vehicle speed is based on the wheel speed of the front wheel when the parking brake is activated and based on the wheel speed of the rear wheel when the parking brake is not activated. To calculate. Therefore, the vehicle speed can be calculated accurately.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS.
Will be described. First, the structure of the vehicle brake device of the present invention will be described with reference to FIG. In FIG.
1FL is left front wheel, 1FR is right front wheel, 1RL is left rear wheel, 1
RR is the right rear wheel. The engine 2 is mounted horizontally on the front part of the vehicle body, and the torque generated by the engine 2 is transmitted to the clutch 3, the transmission 4, and the differential gear, and then to the left front wheel 1FL via the left drive shaft 6L. Further, they are respectively transmitted to the right front wheel 1FR via the right drive shaft 6R. As described above, this vehicle is a so-called FF vehicle in which the front wheels 1FL and 1FR are the driving wheels and the rear wheels 1RL and 1RR are the driven wheels.

Reference numerals 7FR to 7RR are brakes mounted on respective wheels, and the brakes 7FR to 7RR are hydraulic disc brakes. The master cylinder 8 as a brake pressure generation source is a tandem type and has two discharge ports 8a and 8b. A brake pipe 13 extends from one discharge port 8a of the master cylinder 8, and the brake pipe 13 is branched into two on the way.
F is connected to the left front wheel brake 7FL and is connected to the branch pipe 13
R is connected to the right rear wheel brake 7RR. From the other discharge port 8b of the master cylinder 8, the brake pipe 1
4, the brake pipe 14 is also branched into two in the middle, the branch pipe 14F is connected to the right front wheel brake 7FR, and the branch pipe 14R is connected to the left rear wheel brake 7RL.

Further, branch pipes 13F, 1 for these front wheels are provided.
4F includes a hydraulic pressure adjustment valve 15L and a pipe 2 that constitute a brake pressure adjustment device that performs brake control during traction control.
1L, reservoir tank 22L, pump 23L, check valve L, pipe 25L, hydraulic pressure adjusting valve 15R, pipe 21R,
A reservoir tank 22R, a pump 23R, a check valve R, and a pipe 25R are provided respectively. The branch pipes 13R and 14R for the rear wheels are provided with open / close valves 16L and 16R, respectively.

The master cylinder 8 is provided with a brake booster 11 which is a booster, and the stepping force on the brake pedal 12 is transmitted to the master cylinder 8 via the brake booster 11. This booster 1
As will be described later, 1 is configured to function as a stop brake 30 that performs a boosting action even when the brake pedal 12 is not depressed when the vehicle is stopped.

The booster 11 has a case 31 fixed to the vehicle body and the master cylinder 8, and inside this case 31.
However, due to the diaphragm 32 and the valve body 33 fixed to the diaphragm 32, the first chamber 34 and the second chamber 3 are
It is divided into five. An input shaft 36 connected to the brake pedal 12 is connected to the valve body 33, and an output shaft 37 connected to the master cylinder 8 is connected to the valve body 33. Reference numeral 38 is a return spring that biases the valve body 33 rearward (rightward in the drawing). Reference numeral 40 denotes a pressure introducing passage, and one end of the pressure introducing passage 40 communicates with the second chamber 35 via a space formed in the valve body 33. A three-way electromagnetic switching valve 41 is provided at the other end of the pressure introducing passage 40, and a pipe 42 communicating with the first chamber 34 is connected to the three-way electromagnetic switching valve 41. Here, the first chamber 34 always has a negative pressure (for example, the engine 2
Intake negative pressure) is being supplied. In addition, three-way solenoid switching valve 4
1 was switched so that the second chamber 35 communicated with the first chamber 34 via the pressure introduction passage 40 and the pipe 42 during demagnetization so as to be maintained in vacuum, and during excitation, the first chamber 34 was maintained in vacuum. In the state, switching is performed so that the atmospheric pressure is introduced into the second chamber 35 through the pressure introducing passage 40.

In the brake booster 11 constructed as described above, first, the brake pedal 12 is operated while the vehicle is running.
When the stepping operation is not performed, the first chamber 34 and the second chamber 35 are in communication with each other through the pressure introducing passage 40, the three-way electromagnetic switching valve 41 and the pipe 42, and the operation of the booster 11 is stopped. Becomes When the brake pedal 12 is depressed, the atmosphere is supplied to the second chamber 35 from the right side of the valve body 33, whereby the diaphragm 32 is displaced forward together with the valve body 33, and a boosting function is exerted.

Next, the case where the brake booster 11 functions as the stop brake 30 will be described. When the vehicle is stopped and the conditions described below are further satisfied, the three-way electromagnetic switching valve 41 is excited and the first chamber 34 is kept in a vacuum state. Atmospheric pressure is introduced. As a result, even if the brake pedal 12 is not depressed, the diaphragm 32 is moved to the valve body 33.
Along with this, it is displaced forward and the boosting function is exerted.

Here, 10 is an accelerator pedal, 50 is a parking brake, and 51 is a control unit. Also S
1 to S4 are wheel speed sensors that detect the rotational speeds of the wheels 1FR to 1RR, S5 is a sensor that detects whether or not the accelerator pedal 10 is depressed, and S6 is whether or not the parking brake 50 is operating. It is a sensor. Next, the control content will be described with reference to FIG. In FIG. 2, P indicates each step. At P1, it is determined whether the vehicle is stopped. In this embodiment, the vehicle speed calculated by the wheel speed sensors S1 to S4 is 3 km /
If h or less and the brake pressure is a predetermined value or more, it is determined that the vehicle is stopped.

When it is determined that the vehicle is stopped, P
Then, the procedure proceeds to step 2 to determine whether "F = 0". Here, "F
= 0 ”indicates that the stop brake is not operating, and“ F = 1 ”
Indicates the operating state of the stop brake. In P2, when "F = 0", that is, when the stop brake is inactive, it is determined in P3 whether or not the parking brake is in operation. If the parking brake is activated,
In P4, it is determined whether or not the parking brake is released. If the parking brake is further released, it is determined in P5 whether or not a predetermined time has elapsed since the parking brake was released. Here, until the predetermined time passes, the stop brake is deactivated after the parking brake is released.

After the lapse of a predetermined time, it is determined whether or not the parking brake is in operation at P3 via P1 and P2. If the parking brake is not in operation, P
In 6, the stop brake is activated, and in P7, “F =
1 ”is set. In P2, when "F = 1", that is, when the stop brake is determined to be in the operating state, the process proceeds to P8, in which it is determined whether or not the parking brake is operating.
If it is not in operation, the routine proceeds to P9, where it is judged if the accelerator pedal is depressed. When the accelerator pedal is depressed, the stop brake is released at P10 and P1 is released.
At 1, "F = 0" is set. Here, in P8,
If the parking brake is in operation, the process goes directly to P10 without going through P9.

When it is determined at P1 that the vehicle is not stopped, that is, the vehicle is running, the program proceeds to P12 and "F
= 0 ”is determined. When "F = 1", that is, when it is determined that the stop brake is in the operating state, the process proceeds to P10, and the stop brake is released. In the embodiment of the present invention configured as described above, the stop brake is released when the vehicle is stopped and the parking brake is activated (P2,
(P8, P10), when the parking brake is not operated, the stop brake is operated in principle (P6). However, even when the parking brake is not activated, the stop brake is released in the following cases. That is, when the driver depresses the accelerator pedal when the vehicle is stopped, the driver is trying to start. Therefore, in such a case, the stop brake is released even when the parking brake is not operated ( P9, P10). Further, after the parking brake is released, the stop brake is released until a predetermined time elapses (P4, P5). At this time, the stop brake is activated after a predetermined time has elapsed (P6).

Thus, since the stop brake is released until a predetermined time elapses after the parking brake is released, when the automatic vehicle restarts after the vehicle is stopped, the automatic transmission is set to the D range or It is possible to drive on a flat road or a slope without shifting the accelerator while shifting to the N range. Also, the vehicle speed is 3
If the braking pressure is less than km / h and the braking pressure is more than a predetermined value,
Since it is determined that the vehicle is stopped, it can be reliably determined that the vehicle is stopped.

Further, in the present invention, in the case of a so-called FF vehicle in which the front wheels of the vehicle are the driving wheels and the rear wheels are the driven wheels, when the vehicle speed is estimated and calculated by the wheel speed sensors S1 to S4, normally The vehicle speed may be estimated by the rear wheels that are the driving wheels, and the vehicle speed may be estimated by the front wheels that are the driving wheels when the parking brake is activated. Since the parking brake is configured to act on the rear wheels that are the driven wheels,
By estimating the vehicle speed in this way, it is possible to accurately estimate the vehicle speed.

[0022]

【The invention's effect】 [Brief description of drawings]

FIG. 1 is a configuration diagram showing an entire vehicle to which a vehicle brake device of the present invention is applied.

FIG. 2 is a flowchart showing the control contents of the vehicle brake device of the present invention.

[Explanation of symbols]

 8 master cylinder 10 accelerator pedal 11 brake booster 12 brake pedal 30 stop brake 40 pressure introduction passage 41 three-way electromagnetic switching valve 42 piping 50 parking brake 51 control unit 7FR to 7RR brake S1 to S6 sensor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Seiji Miyamoto 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Motor Corporation

Claims (3)

[Claims] 1. A parking device for a vehicle, comprising a parking brake and a brake, wherein the brake operates as a stop brake when the parking brake is not operated and when the vehicle is stopped. A brake device for a vehicle, wherein a brake is deactivated and then a stop brake is activated. 2. The brake device for a vehicle according to claim 1, wherein when the vehicle speed is below a predetermined value and the brake pressure is above a predetermined value, it is determined that the vehicle is stopped. 3. When the front wheel of the vehicle is a driving wheel and the rear wheel is a driven wheel, the wheel speed of the front wheel is set when the parking brake is activated,
The vehicle brake device according to claim 1, wherein the vehicle speed is calculated based on the wheel speeds of the rear wheels when the parking brake is not operated.