JPH08175347A - Brake system having automatic brake device - Google Patents

Abstract

PURPOSE: To decrease the number of part items, to eliminate the need for mounting space, and to achieve further cost reduction by eliminating the need for a pressure source exclusively for automatic braking. CONSTITUTION: During automatic braking, an ECU 36 restricts an electric- controlled variable throttle 25, thus generating pressure in power-steering operating fluid. This pressure causes closing of first and second brake passage switching valves 18, 19, and also causes lowering of the first and second pistons 30a, 31a of first and second automatic brake cylinders 30, 31, thereby generating brake pressure for the automatic braking. This brake pressure is supplied to first to fourth wheel cylinders 6, 7, 13, 14 via seventh and eighth passages 28, 29, first and second passages 8, 15 and via first to fourth branch passages 9, 10, 16, 17 so that first to fourth wheels 4, 5, 11, 12 are braked automatically with braking forces that match the amount of restriction of the electric- controlled variable throttle 25. Thus the need for a pressure source exclusively for automatic braking is eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention makes it possible to easily start a vehicle, such as an automobile, on a slope, and to eliminate the need to wait for a signal or to continue to depress the brake pedal on a congested road. In order to control the traction during idling of the vehicle, to keep the vehicle stopped on a slope, to control the distance between vehicles while traveling, to suppress the traveling speed of the vehicle such as overspeed prevention on a downhill, or on the side The present invention relates to a brake system including an automatic braking device used to prevent forgetting to apply a brake.

[0002]

2. Description of the Related Art Recently, in automobiles, it is possible to easily start a vehicle such as an automobile on a slope without requiring a sudden pedal change operation from a parking brake or a brake pedal to an accelerator pedal. For,
In order to reduce the fatigue caused by brake operation by eliminating the need to operate the brake pedal while waiting for traffic lights and in congested roads, traction control should be performed when the drive wheels run idle to ensure proper start and acceleration. In order to ensure that the vehicle is stopped on a hill, the inter-vehicle distance is automatically controlled while driving, and the vehicle traveling speed is controlled to prevent overspeed on a downhill. An automatic brake device has been developed that is used for automatically preventing the vehicle from forgetting to apply a side brake.

As an example of a brake system provided with such an automatic brake device, there is a brake system as shown in FIG. In the figure, 51 is a brake pedal, 52 is a negative pressure booster, 53 is a tandem master cylinder, 54,
55 is a wheel cylinder, 56 and 57 are wheels, and 58 and 59
Is a double check valve, 60 is an electromagnetic switching valve, 61 is an electromagnetic control unit (ECU), 62 is a pressure source, 63 is a pump,
64 is an accumulator, 65 is a check valve, and 66 is a reservoir.

In the normal brake of the brake system including the automatic brake device having such a structure, the negative pressure booster 52 is set to a predetermined level by depressing the brake pedal 51 from the brake non-operating state shown in FIG. The brake pedal 51 stepping force is boosted by the servo ratio and output, and this output causes the tandem master cylinder 53 to generate a brake pressure, which is the double check valve 5.
It is supplied to the wheel cylinders 54, 55 via 8, 59 and the wheels 56, 57 are normally braked. Also,
When the brake is released, the brake pedal 51 is released, so that the negative pressure booster 52 and the tandem master cylinder 53 are deactivated, and the wheel cylinders 54, 5 are released.
The brake fluid of No. 5 is returned to the reservoir 53a of the tandem master cylinder 53 via the double check valves 58, 59, and the normal braking of the wheels 56, 57 is released.

On the other hand, in the automatic braking of the automatic braking device, when the vehicle is in the automatic braking operating condition in the brake non-operating state shown in FIG. 4, the ECU 61 detects this and switches the electromagnetic switching valve 60. As a result, the pressure source 6
The accumulator pressure of the accumulator 64 in which a predetermined pressure is accumulated by the second pump 63 is supplied as brake pressure to the wheel cylinders 4 and 5 via the electromagnetic switching valve 10 and the double check valves 8 and 9 and is automatically applied to the wheels 56 and 57. The brake is applied. When the automatic brake operating condition is resolved, the ECU 61 detects this and switches the electromagnetic switching valve 60 to the initial position. As a result, the brake fluid in the wheel cylinders 54, 55 passes through the double check valves 58, 59 and the electromagnetic switching valve 60, and the reservoir 6
Then, the automatic braking of the wheels 56 and 57 is released. Thus, the automatic braking device can perform normal braking as well as automatic braking.

[0006]

By the way, such a conventional automatic brake device requires a dedicated pressure source 62 for automatic brake operation. This pressure source 6
No. 2 requires various parts such as a pump 63, an accumulator 64, a check valve 65, and a reservoir 66, and not only has a large number of parts, but also has a problem that the cost is high and a large mounting space is required.

The present invention has been made in view of the above problems, and an object thereof is to eliminate the need for a dedicated pressure source for automatic braking, thereby reducing the number of parts and mounting space. It is an object of the present invention to provide a brake system equipped with an automatic brake device that is unnecessary and can be manufactured at a lower cost.

[0008]

In order to solve the above-mentioned problems, the invention of claim 1 is a brake operating member, and a master cylinder for generating a brake pressure of a normal brake by the brake operation of the brake operating member. A first brake passage for supplying the brake pressure of the normal brake;
A brake cylinder that is supplied with the brake pressure of the normal brake to generate a braking force for braking the wheels, a power steering device that generates an auxiliary steering force according to the steering of the steering wheel, and a power steering system for the power steering device. A power steering system that includes a pump that supplies hydraulic fluid to assist the steering with the auxiliary steering force, and a power steering hydraulic fluid that is disposed in a power steering passage through which the power steering hydraulic fluid flows. Pressure generating means for generating a pressure, automatic brake pressure generating means for generating a brake pressure of an automatic brake by the pressure generated by the pressure generating means, and brake pressure of the automatic brake connected to the first brake passage. Second supply to the first brake passage A rake passage and a normally open first brake passage which is provided in the first brake passage on the master cylinder side of the connection point between the first brake passage and the second brake passage and which is normally opened and closed when the pressure generating means is activated. It is characterized by comprising an opening / closing valve No. 1 and a control device for controlling the operation of the pressure generating means.

According to a second aspect of the present invention, the pressure generating means is an electrically controlled variable throttle for generating a pressure corresponding to the throttle amount in the power steering hydraulic fluid, and the automatic brake pressure generating means is the electric control. An automatic brake cylinder that generates a brake pressure of the automatic brake in response to a pressure generated by a variable throttle, wherein the first opening / closing valve is an opening / closing valve that is closed by the pressure generated by the electrically controlled variable throttle, The control device is an electronic control device that controls the operation of the electrically controlled variable throttle when the automatic brake operating condition is satisfied.

Further, according to the invention of claim 3, the two brake systems are provided and the master cylinder is formed as a tandem master cylinder, and the first brake passage,
The brake cylinder, the automatic brake cylinder,
The second brake passage and the first opening / closing valve are provided for each of the two brake systems.

Further, in the invention of claim 4, a check valve for allowing only the flow of the brake fluid from the tandem master cylinder to the brake cylinder is provided in a passage bypassing the first opening / closing valve for each brake system. It is characterized by being.

Further, in the fifth aspect of the invention, the first brake passage between the first on-off valve and the brake cylinder is normally open and normally open and is normally operated and closed by the electronic control unit. The second opening / closing valve is provided for each brake system.

According to a sixth aspect of the present invention, the brake cylinder of one brake system of the two brake systems is provided corresponding to a drive wheel, and the brake cylinder of the other brake system of the two brake systems is provided. Is provided corresponding to the driven wheel.

Further, in the invention of claim 7, the brake cylinders provided corresponding to the drive wheels are provided independently for each of the left and right drive wheels, and the first brake of the one brake system is provided. The passage is branched immediately before the brake cylinders corresponding to the left and right drive wheels into first and second branch passages connected to these brake cylinders, and the second opening / closing valve of the one brake system is the first opening / closing valve. And is provided in the second branch passage.

[0015]

In the present invention thus constituted, the normal brake is operated by the brake operation of the brake operation member.
The master cylinder generates the brake pressure of the normal brake,
This brake pressure is supplied to the brake cylinder via the first brake passage and the normally open first opening / closing valve, and normal braking is performed.

Further, when the automatic brake operating condition is satisfied, the control device operates the pressure generating means, and by the operation of the pressure generating means, the first opening / closing valve is closed and pressure is generated in the power steering hydraulic fluid. Thus, the automatic brake pressure generating means generates the brake pressure of the automatic brake. This brake pressure is applied to the second brake passage and the first brake passage.
It is delivered to the brake cylinder via the brake passage,
Automatic braking is performed. At this time, since the first on-off valve is closed, the brake pressure of the automatic brake generated by the automatic brake pressure generating means does not leak to the master cylinder, and therefore the loss of the brake pressure of the automatic brake is prevented. It

Further, when the automatic brake operating condition is satisfied during the normal brake operation, the first opening / closing valve is closed and the automatic brake pressure generating means generates the brake pressure of the automatic brake by the operation of the pressure generating means as described above. To do.
As a result, the brake pressure of the automatic brake is added to the brake pressure of the normal brake to increase the overall brake pressure. In this state, even if the brake operation of the brake operation member is released, the automatic brake is kept in operation,
The brake pressure at this time is the increased brake pressure described above.

Particularly, in the invention of claim 4, when the normal brake is operated by the brake operation of the brake operation member during the automatic brake operation, the master cylinder generates the brake pressure as described above. When this brake pressure becomes higher than the brake pressure of the automatic brake, the brake pressure of the master cylinder is sent to the brake cylinder through the first brake passage and the check valve, and the brake pressure becomes higher, and the normal brake operates together with the automatic brake. To do. This increases the braking force.

In the fifth aspect of the invention, when the electronic control unit determines that the brake holding condition is satisfied during the normal brake or automatic brake operation, the electronic control unit closes the second opening / closing valve. As a result, the brake is held in the activated state.

Further, according to the invention of claim 6, it becomes possible to perform traction control. That is, when the electronic control unit determines that the drive wheels tend to idle, the electronic control unit closes the second opening / closing valve of the brake system corresponding to the driven wheels and operates the electric opening / closing variable throttle. As a result, the automatic brake cylinders of the two-brake system both generate brake pressure. The brake pressure of the brake system corresponding to the drive wheel is supplied to the brake cylinder corresponding to the drive wheel because the second opening / closing valve of the brake system is not closed, and the drive wheel is braked. Accordingly, the rotational driving force of the drive wheels is suppressed and controlled so that the idling tendency of the drive wheels is eliminated. At this time, since the second opening / closing valve of the brake system corresponding to the driven wheel is closed, the brake pressure generated by the automatic brake cylinder is not supplied to the brake cylinder corresponding to the driven wheel, and the driven wheel is not braked. I can't call it. Thus
Traction control is performed on the drive wheels.

Further, in the invention of claim 7, the traction control can be independently performed for each of the left and right drive wheels. Further in the present invention,
Even if the hydraulic circuit of the power steering system or the electrically controlled variable throttle fails, normal braking is performed by depressing the brake pedal.

By the way, in the present invention, the pressure source of the existing power steering system is used as the pressure source of the automatic braking device. Therefore, a dedicated pressure source for the automatic braking device is not necessary, and the structure is extremely simple.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a first embodiment of an automatic braking device according to the present invention. This first, as shown in FIG.
The automatic brake device of the embodiment is a brake pedal 1 for applying a normal brake as in the conventional normal brake device, and a conventionally known negative pressure booster that boosts the pedaling force of the brake pedal at a predetermined servo ratio and outputs the boosted force. Device 2, a conventionally known tandem master cylinder 3 that operates by the output of the negative pressure booster 2 to generate a brake pressure, and brake pressure from one pressure chamber (not shown) of the tandem master cylinder 3 to two wheels. A first passage 8 having one end connected to one pressure chamber of the master cylinder for supplying to the wheel cylinders 6 and 7 of the master cylinder 4 and the other end of the first passage 8 respectively branched to the wheel cylinders 4 and 5. The brake pressure from the first and second branch passages 9 and 10 connected to the tandem master cylinder 3 and the other pressure chamber (not shown) of the tandem master cylinder 3 is applied to the two wheels 1 and 2.
A second one whose one end is connected to the other pressure chamber of the master cylinder in order to supply it to the one and twelve wheel cylinders 13 and 14.
The passage 15 and third and fourth branch passages 16 and 17 branched from the other end of the second passage 15 and connected to the wheel cylinders 13 and 14 are provided. First and second
The passages 8 and 15 form the first brake passage of the present invention.

Further, in the brake system including the automatic brake device of the first embodiment, the normally open first and second normally open brake passage opening / closing valves 18 and 19 constituting the first opening / closing valve of the present invention are respectively the first and second brake passage opening / closing valves. The first and second passages 8 and 15 are arranged, and the first and second brake passage opening / closing valves 18 and 19 are normally open as will be described later. It is set to be closed by the pressure of the power steering hydraulic fluid boosted by the electrically controlled variable throttle 25 supplied through

Further, in this automatic braking device, as in the conventionally known power steering system, the power steering hydraulic fluid reservoir 20 for storing the hydraulic fluid for power steering, and the power for sucking the power steering hydraulic fluid in the reservoir 20. The steering pump 21 and a well-known power for generating an auxiliary steering force of the steering wheel by generating a power steering pressure in the power steering hydraulic fluid supplied from the power steering pump 21 through the third passage 22 in accordance with the steering amount of the steering wheel. The steering device 23 and a fourth passage 24 that is a return line for discharging the power steering hydraulic fluid from the power steering device 23 to the reservoir 20 are provided.

An electrically controlled variable throttle 25, which is the pressure generating means of the present invention, is disposed in the fourth passage 24, and normally the power steering hydraulic fluid flowing through the fourth passage 24 is not throttled at all. By squeezing the power steering hydraulic fluid flowing through the fourth passage 24 during automatic braking, pressure is generated upstream of the electric control variable throttle 25.

Further, in the fourth passage 24 upstream of the electrically controlled variable throttle 25, one side of the first and second automatic brake cylinders 30, 31 is provided with the fifth and sixth passages 2, respectively.
6 and 27, and the other sides of the first and second automatic brake cylinders 30 and 31 are connected to the first and second brake passage opening / closing valves 18 and 18 via the seventh and eighth passages 28 and 29, respectively. , 19 are connected to the first and second passages 8 and 15 on the downstream side. These first and second automatic brake cylinders 30 and 31 move downward in the drawing when their first and second pistons 30a and 31a receive the pressure of the power steering hydraulic fluid on the upstream side of the electric control variable throttle 25. By doing so, the brake fluid is set to generate a brake pressure. The first and second pistons 30a and 31a are liquid-tightly slidable on the first and second automatic brake cylinders 30 and 31 by the first and second O-rings 30b and 31b, and the spring 30b. , 31b are always urged upward, but when no pressure is generated in the power steering hydraulic fluid on the upstream side of the electric control variable throttle 25, these pistons 30a, 31a are provided with appropriate stoppers (not shown) or the like. It is restricted to the upper limit position shown in the figure by the restriction means, and no brake pressure is generated. In addition, the first and second pistons 30a and 31a
The O-rings 30b and 31b prevent the hydraulic fluid of the power steering made of mineral oil from mixing with the brake fluid made of vegetable oil. Furthermore, the seventh and eighth passages 28,
Reference numeral 29 constitutes the second brake passage of the present invention, and also includes the first and second automatic brake cylinders 30, 31.
Constitutes the automatic brake pressure generating means of the present invention.

Furthermore, the first of the first and second passages 8, 15
And the 9th and 10th passages 32, 3 where the upstream side and the downstream side of the 2nd brake passage opening / closing valves 18, 19 bypass the 1st and 2nd brake passage opening / closing valves 18, 19 respectively.
Connected through the third and the ninth and tenth of these.
First and second check valves 34 and 35 are provided in the passages 32 and 33, respectively. These first and second check valves 34, 35 allow only the flow of brake fluid from the tandem master cylinder 3 to the wheel cylinders 6, 7, 13, 14 and prevent the reverse flow of brake fluid. Is set to.

Further, an electronic control unit (hereinafter, also referred to as an ECU) 36 for controlling the operation of the electric control variable throttle 25 is provided, and this ECU 36 is, for example, each wheel speed sensor,
Calculated based on the signals from the clutch stroke sensor, clutch switch, neutral switch, stop lamp switch, parking brake switch, and door switch. Aperture 25
Is controlled to generate pressure in the power steering hydraulic fluid upstream of the electrically controlled variable throttle 25. The automatic brake operating conditions include the conditions for starting a slope, the conditions for holding a braking condition in a signal waiting state and a traffic jam, the conditions for performing traction control, and the conditions for holding a vehicle stopped on a slope. There are conditions, conditions for controlling the inter-vehicle distance during traveling, conditions for suppressing the traveling speed of the vehicle, conditions for preventing forgetting to apply the side brake, and the like.

In the automatic brake device of the first embodiment having such a configuration, the power steering hydraulic fluid flowing through the fourth passage 24 is not throttled by the electrically controlled variable throttle 25 when the illustrated brake is not operated. Therefore, no pressure is generated in the power steering hydraulic fluid upstream of the electric control variable throttle 25, and the pistons 30a and 31a of the first and second automatic brake cylinders 30 and 31 are not generated.
Is in the upper limit position shown, and the first and second brake passage opening / closing valves 18 and 19 are in open positions.

When the brake pedal 1 is depressed in order to apply the normal brake in this state, the negative pressure booster 2 boosts the pedal effort with a predetermined servo ratio and outputs the boosted pedal effort, which causes the tandem master cylinder 3 to output. Brake pressure is generated in the two pressure chambers. The brake pressure in one pressure chamber is
The first passage 8, the open first brake passage opening / closing valve 18,
The first and second branch passages 9 and 10, and the first passage 8 through the ninth passage 32, the first check valve 34, and the first and second branch passages 9 and 10, respectively.
It is supplied to the wheel cylinders 6, 7 and the first and second wheels 4, 5 are normally braked. At this time, the first
The automatic brake cylinder 30 has a first piston 30.
Since a does not move upward, that is, does not move toward one side of the first automatic braking cylinder 30, its volume does not increase, and therefore the brake is activated with almost no delay. Similarly, the brake pressure in the other pressure chamber of the tandem master cylinder 3 also changes from the second passage 15, the open second brake passage opening / closing valve 19, the third and fourth branch passages 16 and 17, and the second passage 15 to the second passage 15. 10th passage 33, 2nd check valve 35, 3rd and 4th branch passage 16,17 is supplied to the 3rd and 4th wheel cylinder 13,14, respectively, 3rd and 4th wheel 1
Brakes 1 and 12 are normally applied. At this time, the second
The automatic braking cylinder 31 has its second piston 31.
Since b does not move upward, that is, does not move toward one side of the second automatic brake cylinder 31, its volume does not increase, and therefore the brake is activated with almost no delay.

When the brake pedal 1 is released to release the normal brake, the negative pressure booster 2 becomes inactive and each pressure chamber of the tandem master cylinder 3 communicates with the reservoir 3a. The brake fluid supplied to the fourth wheel cylinders 6, 7, 13, 14 is supplied from the first to fourth branch passages 9, 10, 16, 17 to the first and second brake passages.
No flow through check valves 34, 35, but first
Or through the first and second passages 8,15 from the fourth branch passages 9,10,16,17, the open first and second brake passage opening / closing valves 18,19, and the first and second passages 8,15 , And returns to each pressure chamber of the tandem master cylinder 3 and the reservoir 3a, and the normal brake is released.

When the ECU 36 determines that the automatic brake operating condition is satisfied based on the detection signals from the various sensors in the brake non-operating state shown in the figure, the ECU 36 sets the electric control variable throttle 25 by the throttle amount corresponding to the determination result. squeeze.
As a result, a pressure according to the throttle amount is generated in the power steering hydraulic fluid on the upstream side of the electrically controlled variable throttle 25. This pressure closes the first and second brake passage opening / closing valves 18 and 19, and the first and second pistons 3 of the first and second automatic brake cylinders 30 and 31.
0a, 31a moves downward by an amount corresponding to the pressure, that is, moves to the other side of the first and second automatic brake cylinders 30, 31 to generate brake fluid below the first and second pistons 30a, 31a. A brake pressure corresponding to the pressure is generated. This brake pressure is applied to the seventh and eighth passages 28,2.
9, the first and second passages 8 and 15, and the first to fourth branch passages 9, 10, 16 and 17 are supplied to the first to fourth wheel cylinders 6, 7, 13 and 14 to supply the first to fourth passages. Electrically controlled variable aperture 2 is attached to each of the fourth wheels 4, 5, 11 and 12.
Automatic braking is applied with a braking force according to the throttle amount of 5. To increase the braking force of the automatic brake, the throttle amount of the electric control variable throttle 25 may be reduced, and to decrease the braking force of the automatic brake, the throttle amount of the electric control variable throttle 25 may be increased. .

First and second automatic braking cylinders 3
The brake pressures generated at 0 and 31 are the same as those of the closed first and second brake passage opening / closing valves 18 and 19 and the first and second brake passage opening / closing valves 18 and 19, respectively.
Since the check valves 34 and 35 prevent leakage toward the first and second passages 8 and 15, the first to fourth wheel cylinders 4,5, 11 and 1 can be maintained without loss.
2, the automatic braking is effectively applied.

When the automatic brake operating condition is canceled, EC
U36 releases the diaphragm of the electrically controlled variable diaphragm 25 to deactivate it. As a result, the pressure of the power steering hydraulic fluid on the upstream side of the electrically controlled variable throttle 25 is reduced to the inoperative state. Then, the first and second brake passage opening / closing valves 18,
19 is opened and the first and second pistons 30a and 31 of the first and second automatic brake cylinders 30 and 31 are opened.
a returns to the inoperative position. As a result, the brake pressure of the first to fourth wheel cylinders 6, 7, 13, 14 is reduced,
The automatic brake is released.

When the automatic brake operating condition is satisfied during the normal brake operation by depressing the brake pedal 1,
Similarly to the above, the ECU 36 throttles the electric control variable throttle 25 to generate pressure in the power steering hydraulic fluid. When this pressure becomes larger than the brake pressure at the time of normal brake operation, the first and second pistons 30a and 31a move downward, the brake pressure of the automatic brake is added to the brake pressure of the normal brake, and the overall brake pressure is further increased. growing. Thus, the automatic brake operates together with the normal brake. In this state, even if the brake pedal 1 is released and the normal brake is released, automatic braking is performed by the closed first and second brake passage opening / closing valves 18 and 19 and the first and second check valves 34 and 35. It is kept active. Further, the release of the automatic brake at this time is the same as that in the case of the automatic brake described above.

When the automatic brake is operated, if the normal brake is operated by depressing the brake pedal 1 in order to further increase the braking force, the brake pressure is generated in each pressure chamber of the tandem master cylinder 3 as described above. When the brake pressure generated in these pressure chambers becomes larger than the brake pressure of the automatic brake, the brake pressure generated in the pressure chambers passes through the first and second passages 8 and 15 and the first and second check valves 34 and 35. The brake pressure is sent to the first to fourth wheel cylinders 6, 7, 13, 14 to further increase the brake pressure, and the normal brake operates together with the automatic braking. This increases the braking force. In this state, even if the automatic brake is released, the brake pedal 1 is stepped on, so that the normal brake is kept in operation. Further, the release of the normal brake after the release of the automatic brake is the same as the case of the above-described normal brake because the first and second brake passage opening / closing valves 18 and 19 are opened.

Further, even when the hydraulic circuit of the power steering system or the electrically controlled variable throttle 25 fails, normal braking is performed by depressing the brake pedal 1.

As described above, according to the automatic brake device of the first embodiment, since the pressure source of the existing power steering system is used as the pressure source of the automatic brake device, it is dedicated to the automatic brake device. Since the pressure source is not required and only the electrically controlled variable throttle 25 and the first and second automatic brake cylinders 30 and 31 are provided, the configuration is extremely simple and the cost can be reduced.

Further, since the normal brake can be operated and the braking force can be increased by depressing the brake pedal 1 during the automatic braking operation, even if the braking force due to the automatic braking is insufficient, the braking force is surely applied. Can be activated.

Further, since the automatic brake can be operated during the normal brake operation, even if the driver releases the brake pedal 1 without knowing it when the automatic brake operation condition is reached, the automatic brake is in the operating state. Can be held at.

Further, even if the hydraulic circuit of the power steering system or the electrically controlled variable throttle 25 fails, the normal braking can be performed, so that the brake can be operated safely and reliably.

FIG. 2 shows a first embodiment of the present invention, which is a first embodiment.
It is a figure similar to an Example. The same components as those in the first embodiment described above are designated by the same reference numerals, and detailed description thereof will be omitted.

In contrast to the first embodiment described above, in this second embodiment, as shown in FIG. 2, the normally open first and second electromagnetic on-off valves 37, 37, which constitute the second on-off valve of the present invention, 38
Is a connection point between the seventh and eighth passages 28 and 29 and the first and second passages 8 and 15, and a connection point between the seventh and eighth passages 28 and 29 and the ninth and tenth passages 32 and 33, respectively. Located in the first and second passages 8, 15 between the points. These first and second solenoid on-off valves 37, 38 are E
It is electrically connected to the CU 36 and is closed by the ECU 36 when a brake holding condition is established. The other configurations of the second embodiment are the same as those of the first embodiment.

In the automatic brake device of the second embodiment thus constructed, the normal brake operation, the automatic brake operation, the automatic brake operation during the normal brake operation, and the normal brake operation during the automatic brake operation are performed in the first embodiment. Since they are the same as those of the automatic braking device of No. 1, the description thereof will be omitted.

Further, in the second embodiment, when the ECU 36 determines that the brake holding condition is satisfied by the detection signals from various sensors during the normal brake or the automatic brake operation, the ECU 36 brakes the brake holding condition being satisfied. The electromagnetic on-off valves 37 and 38 of the system are closed. As a result, the brakes of this brake system are maintained in the activated state. The effect of the second embodiment can be the same as that of the first embodiment, and the brake operation holding state can be achieved when necessary.

FIG. 3 shows the first embodiment of the third embodiment of the present invention.
FIG. 9 is a view similar to that of the second embodiment. In addition, the above-mentioned first
The same components as those in the second embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

In the second embodiment described above, the two brake systems are set regardless of the drive wheels and the driven wheels, whereas in the third embodiment, one brake system is provided as shown in FIG. The left and right drive wheels 39, 40 are set, and the other brake system is set for the left and right driven wheels 41, 42. Further, in the third embodiment, the first electromagnetic on-off valve 37 of the second embodiment is eliminated, and the normally open third and fourth electromagnetic on-off valves 43 and 44 are respectively the first and the second.
It is provided in the branch passages 9 and 10. These third and fourth electromagnetic on-off valves 43 and 44 are electrically connected to the ECU 36, and when at least one of the drive wheels 39 and 40 has a tendency to idle, the ECU 36 does not tend to idle. Solenoid on-off valve 43 corresponding to 39, 40,
44 is adapted to be closed. The other configurations of the third embodiment are the same as those of the second embodiment.

In the automatic brake device of the third embodiment having such a configuration, the normal brake operation, the automatic brake operation, the automatic brake operation during the normal brake operation, and the normal brake operation during the automatic brake operation are performed in the first embodiment. Since they are the same as those of the automatic braking device of No. 1, their explanations are omitted.

Further, in the third embodiment, when the ECU 36 determines that the wheel brake holding condition is satisfied by the detection signals from various sensors during the normal brake or automatic brake operation, the ECU 36 satisfies the brake holding condition. Solenoid on-off valve 38,4 corresponding to the wheel brake
Close 3,44. As a result, the brake of this wheel is maintained in the activated state.

Further, in the third embodiment, among various sensors, E is determined based on the wheel speed signal from the wheel speed sensor.
When the CU 36 determines that at least one of the left and right drive wheels 39, 40 has tended to idle, the ECU 36 determines that the driven wheel 4 has
The second solenoid on-off valve 38 on the side of 1, 42 is closed, and the solenoid on-off valve 4 corresponding to the drive wheels 39, 40 which are not in the tendency to idle.
Close 3,44. Further, at the same time, the ECU 36
As in the case of the automatic braking described above, the electrically controlled variable diaphragm 2
Squeeze 5 according to the amount of idle rotation. As a result, a pressure corresponding to the throttle amount is generated in the power steering hydraulic fluid on the upstream side of the electric control variable throttle 25, and this pressure closes the first and second brake passage opening / closing valves 18 and 19, and Second automatic brake cylinder 30, 31
A brake pressure corresponding to the pressure is generated in the brake fluid below the first and second pistons 30a and 31a. First
The brake pressure of the piston 30a is supplied through the open passage of the seventh passage 28, the first passage 8, the first and second branch passages 9 and 10, and the third and fourth solenoid opening and closing valves 43 and 44. , The drive wheels 39, 40 corresponding to this open solenoid on-off valve, that is, which tend to idle, are braked. As a result, the rotational driving force of the drive wheels 39, 40 that tend to slip is suppressed, and the idling tendency of the drive wheels 39, 40 is eliminated. Thus, in the automatic brake device of the third embodiment, the traction control by the brake on the drive wheels is performed.

The effect of the third embodiment can be the same as that of the first and second embodiments, and further, according to the automatic brake device of the third embodiment, the drive wheels 39, 40.
It is possible to perform traction control on the drive wheels that are idling when the idling tendency of

In the third embodiment, one brake system is associated with the left and right drive wheels 39, 40, and the other brake system is associated with the left and right driven wheels 41, 42. The brake system corresponds to one of the left and right drive wheels 39, 40 and one of the left and right driven wheels 41, 42, and the other brake system corresponds to the other of the left and right drive wheels 39, 40 and the left and right driven wheels 41, 42. It is also possible to correspond to the other of. In this case, in order to perform the traction control, the second electromagnetic on-off valve 38 of the third embodiment is eliminated, and the third embodiment is applied to the first to fourth branch passages 9, 10, 16 and 17, respectively. The same solenoid on-off valves as the third and fourth solenoid on-off valves 43 and 44 of the example are provided, and these solenoid on-off valves are
It is controlled by the CU 36.

In each of the above embodiments, the first
The first and second brake passage opening / closing valves 18 and 19 are formed by mechanical valves that are switched by the pressure generated in the power steering hydraulic fluid by the operation of the electrically controlled variable throttle 25. , 19 can also be formed by electromagnetic opening / closing valves that are switch-controlled by the ECU 36 when the ECU 36 operates the electrically controlled variable throttle 25.

Further, in each of the above-mentioned embodiments, the first
The first and second pistons 30a and 30b of the second automatic brake cylinders 30 and 31 are arranged so that one surface of each piston contacts the hydraulic fluid of the power steering and the other surface contacts the brake fluid. However, these first and second pistons 30a, 30
In b, it is also possible to connect two pistons, a piston in contact with the hydraulic fluid of the power steering and a piston in contact with the brake fluid, with a rod at a predetermined interval.
By configuring each of the first and second pistons 30a and 30b in this manner, there is less risk that the hydraulic fluid of the power steering, which is mineral oil, will mix into the brake fluid that is vegetable oil.

Furthermore, the ninth and tenth passages 32 and 33 and the first and second check valves 34 and 35 in each of the above-mentioned embodiments are not always necessary and can be omitted. However, these 9th and 10th passages 32,
If 33 and the first and second check valves 34 and 35 are omitted, the brake pedal 1 is operated during automatic braking.
The normal brake cannot be actuated by depressing and the brake pressure cannot be increased.

Furthermore, in each of the above-mentioned embodiments, the automatic brake device of the present invention is provided in both of the two brake systems, but one of the two brake systems (in the embodiment shown in FIG. (Only the brake system), and the present invention can be applied to one brake system.

Further, in each of the above-described embodiments, the present invention is applied to the brake system in which the negative pressure booster is used, but the present invention is provided with the power steering system. If it is a braking system for a vehicle that is equipped with a brake system such as a brake system using a hydraulic booster other than the negative booster or a brake system without a booster, It can also be applied to the system.

[0059]

As is apparent from the above description, according to the brake system including the automatic brake device of the present invention, the pressure source of the existing power steering system can be used, so that the traction is achieved. Various automatic braking such as control can be performed. Moreover, according to the present invention, since a dedicated pressure source for automatic braking is not required, the number of parts can be reduced, the configuration is extremely simple, and the cost is reduced.

Further, by operating the brake operating member during the automatic brake operation, the normal brake can be operated. Therefore, even when the braking force due to the automatic braking is insufficient, the braking force can be increased, so that the brake can be operated reliably.

Further, since the automatic brake can be operated during the normal brake operation, even if the driver releases the brake operating member without knowing it when the automatic brake operating condition is reached, the automatic brake is in the operating state. Can be held at.

Furthermore, even when the hydraulic circuit of the power steering system and other parts for automatic braking fail, normal braking can be performed, so that the brake can be operated safely and reliably.

[Brief description of drawings]

FIG. 1 is a diagram showing a first embodiment of a brake system including an automatic brake device according to the present invention.

FIG. 2 is a diagram showing a second embodiment of the present invention.

FIG. 3 is a diagram showing a third embodiment of the present invention.

FIG. 4 is a diagram schematically showing a conventional automatic braking device.

[Explanation of symbols]

1 ... Brake pedal, 2 ... Negative pressure booster device, 3 ... Tandem master cylinder, 4, 5, 11, 12 ... Wheels, 6, 7, 13,
14 ... Wheel cylinder, 8 ... 1st passage, 9 ... 1st branch passage, 10 ... 2nd branch passage, 15 ... 2nd passage, 16 ... 3rd branch passage, 17 ... 4th branch passage, 18 ... 1st brake Passage opening / closing valve, 19 ... second brake passage opening / closing valve, 20 ... power steering hydraulic fluid reservoir, 21 ... power steering pump, 22 ... third passage, 23 ... power steering device, 24 ... fourth passage, 25 ... electricity Control variable throttle, 26 ... fifth passage, 27 ... sixth passage, 28 ... seventh passage, 29 ... eighth passage, 30 ... first cylinder, 31 ... second
Cylinder, 32 ... 9th passage, 33 ... 10th passage, 34 ...
First check valve, 35 ... Second check valve, 36
... electronic control unit (ECU), 37 ... first electromagnetic on-off valve, 3
8 ... 2nd electromagnetic opening / closing valve, 39 ... Left side driving wheel, 40 ... Right side driving wheel, 41 ... Left side driven wheel, 42 ... Right side driven wheel, 43 ... 3rd electromagnetic opening / closing valve, 44 ... 4th electromagnetic opening / closing valve, 45 ... 11th passage, 46 ... 12th passage

Claims (7)

[Claims] 1. A brake operating member, a master cylinder for generating a brake pressure of a normal brake by the brake operation of the brake operating member, a first brake passage for feeding the brake pressure of the normal brake, and the normal cylinder. A brake cylinder that supplies the brake pressure of the brake to generate a braking force for braking the wheel, a power steering device that generates an auxiliary steering force according to the steering of the steering wheel, and a power steering hydraulic fluid to the power steering device. And a power steering system for assisting the steering with the auxiliary steering force, and a pressure for the power steering hydraulic fluid disposed in a power steering passage through which the power steering hydraulic fluid flows. The pressure generation means to generate and this pressure generation Automatic brake pressure generating means for generating a brake pressure of an automatic brake by the pressure generated by the generating means, and a second brake connected to the first brake passage for supplying the brake pressure of the automatic brake to the first brake passage A passage and a first normally open passage that is provided in the first brake passage on the master cylinder side of the connection point between the first brake passage and the second brake passage and that is normally open and that is closed when the pressure generating means is activated. And a control device for controlling the operation of the pressure generating means. 2. The pressure generating means is an electrically controlled variable throttle that generates a pressure corresponding to the throttle amount in the power steering hydraulic fluid, and the automatic brake pressure generating means is generated by the electrically controlled variable throttle. An automatic brake cylinder that receives a pressure to generate a brake pressure of the automatic brake, the first opening / closing valve is an opening / closing valve that is closed by the pressure generated by the electric control variable throttle, and the control device is an automatic brake. A brake system including an automatic brake device according to claim 1, wherein the brake system is an electronic control device that controls the operation of the electrically controlled variable throttle when an operating condition is satisfied. 3. The two-brake system and the master cylinder is formed as a tandem master cylinder, and the first brake passage, the brake cylinder, the automatic brake cylinder, the second brake passage, and the first brake passage. An on-off valve is provided for each brake system of said two brake systems, The brake system provided with the automatic brake device of Claim 2 characterized by the above-mentioned. 4. A check valve that allows only a flow of brake fluid from the tandem master cylinder to the brake cylinder is provided in a passage that bypasses the first opening / closing valve for each brake system. A brake system comprising the automatic brake device according to claim 3. 5. A normally open second on-off valve which is normally open and is normally operated and closed by the electronic control unit in the first brake passage between the first on-off valve and the brake cylinder. Is provided for each brake system, and the brake system provided with the automatic brake device according to claim 3 or 4. 6. The brake cylinder of one brake system of the two brake systems is provided corresponding to a drive wheel, and the brake cylinder of the other brake system of the two brake system corresponds to a driven wheel. A brake system comprising the automatic brake device according to claim 5, wherein the brake system is provided. 7. The brake cylinders provided corresponding to the drive wheels are provided independently for the left and right drive wheels, and the first brake passage of the one brake system is provided for the left and right drive wheels. Immediately before the corresponding brake cylinder, it branches into first and second branch passages connected to these brake cylinders, and the second on-off valve of the one brake system branches into the first and second branch passages. A brake system comprising the automatic brake device according to claim 6, wherein the brake system is provided.