JP3528294B2 - Automatic brake device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brake device for a motor vehicle, and more particularly to an automatic brake device capable of performing a braking operation without depressing a brake pedal.

[0002]

2. Description of the Related Art As a conventional automatic brake device, for example, a device in which a negative pressure type brake booster is improved is known (Japanese Patent Application Laid-Open No. Hei 5-24533). The automatic brake device includes a center plate that partitions the inside of a shell into a front chamber and a rear chamber, a valve body slidably penetrating the center plate, and a front power piston connected to the valve body located in the front chamber. When,
A rear power piston connected to a valve body located in the rear chamber, a front diaphragm stretched behind the front power piston to divide the front chamber into a constant pressure chamber and a variable pressure chamber, and stretched behind the rear power piston. A rear diaphragm for dividing the rear chamber into a constant pressure chamber and a variable pressure chamber; and a valve mechanism formed in the valve body for switching a constant pressure chamber of the front chamber and a fluid circuit. A first constant-pressure passage connecting the constant-pressure chamber of the front chamber to both of the variable-pressure chambers through the first constant-pressure passage, a flexible end connected to the first constant-pressure passage, and the other end drawn out of the shell. Conduit and
A switching valve provided in the conduit for selectively communicating the conduit with a negative pressure source or the atmosphere, and a communication passage located outside the conduit for directly communicating the two constant pressure chambers; .
In such an automatic brake device, when the brake pedal is depressed and the automatic brake device is released, that is, when the braking force is released while the brake booster is kept inoperative, the switching valve is controlled to control What is necessary is just to make the variable pressure chamber communicate with the negative pressure source, and to cut off the communication between the two variable pressure chambers and the atmosphere. As a result, a negative pressure having the same pressure as that of the two constant pressure chambers is introduced into the two variable pressure chambers, so that the brake booster can be maintained in a non-operating state. On the other hand, when the braking force is automatically obtained without operating the brake pedal, the switching valve may be controlled to cut off the conduit from the negative pressure source and to communicate the conduit with the atmosphere. Then, the atmosphere is promptly introduced into the two variable pressure chambers instead of the negative pressure, so that a pressure difference acts on the two power pistons, and the power pistons are advanced forward in the axial direction. To perform the braking action. Further, when the brake pedal is depressed while the automatic brake device is released, the valve mechanism is switched to allow air to be introduced into both of the variable pressure chambers as in the related art. it can. On the other hand, if you depress the brake pedal while operating the automatic brake,
It is communicating with blocking the first pressure passage and both variable pressure chambers, and it has become such that the air and both variable pressure chambers are communicated, after this increase or decrease the braking force in accordance with the increase or decrease of the depression force of the brake pedal Can be.

[0003]

However, if the conduit connecting the switching valve and the two variable pressure chambers is damaged, the air flows into the two variable pressure chambers from the damaged portion, and the brake is doubled when such a failure occurs. The result is that the force device is actuated and braking takes place. The present invention has been made in view of the above circumstances, and provides an automatic brake device that can secure a normal braking operation even when a mechanism for performing an automatic braking operation fails.

[0004]

Means for Solving the Problems] The present invention, blurring
Brake fluid pressure in response to the brake pedal pressure,
Brake fluid pressure to the wheel cylinder to brake
Brake device with a master cylinder that performs the action
In the above, the brake fluid pressure of the master cylinder is
The brake hydraulic pressure chamber to be generated is
The reservoir that connects the brake fluid chamber and the reservoir during operation
A hydraulic pressure generator for supplying hydraulic pressure through a reservoir passage;
A control device for controlling the hydraulic pressure generating device is provided .

[0005]

According to the brake device having the above-described structure, the pressure generated by the hydraulic pressure generator during the automatic braking is the master pressure.
To the wheel cylinder via the cylinder's brake hydraulic chamber
Is supplied, even if the brake pedal is not depressed.
A braking action can be performed dynamically. In the unlikely event that the hydraulic pressure generator or the master cylinder breaks down, the brake system on the master cylinder side is not affected at all and if the brake pedal is depressed, the brake hydraulic pressure And a braking action can be performed.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiment. Referring to FIG. 1, an automatic brake device includes a negative pressure type brake booster 2 for boosting the depressing force of a brake pedal 1, similarly to a conventionally known brake device. A tandem master cylinder 3 that generates a brake fluid pressure according to the increase or decrease in the pedaling force boosted by the brake booster 2. The brake fluid pressure generated by the master cylinder 3 is transmitted through a pipe 4. Is supplied to a wheel cylinder (not shown) to obtain a braking action. The negative pressure type brake booster 2 has a conventionally well-known configuration. As shown in an enlarged view in FIG. 2, a diaphragm 9 is stretched on a back surface of a power piston 8 slidably provided in a shell 7. A negative pressure chamber 10 is formed on the front side and an atmospheric pressure chamber 11 is formed on the rear side. A valve body 1 provided integrally with the shaft of the power piston 8
A valve mechanism 13 for switching the flow path is accommodated in the valve mechanism 2. An input shaft 14 for switching and operating the flow path of the valve mechanism 13 is interlocked with the brake pedal 1, and one end is interlocked with the power piston 8. Seal the other end of the output shaft 15 with the sealing member 1
The tandem master cylinder 3 is interlocked with one of the pistons 21 of the tandem master cylinder 3 by penetrating the shell 6 and projecting out of the shell 7. Further, a negative pressure is constantly introduced into the negative pressure chamber 10 from a negative pressure source 18 such as an intake manifold via a conduit 17.

The tandem master cylinder 3 also has a conventionally well-known structure, and two pistons 21 and 23 are slidably fitted in a cylinder 22 of the master cylinder 3, and usually both springs 24 and 25 Piston 21,
23 are each held in the inoperative position. The rear piston 21 is linked with the output shaft 15 of the brake booster 2 as described above, whereby the piston 21 is moved through the brake shaft via the output shaft 15 and the input shaft 14 of the brake booster 2. It becomes linked to 1. In the cylinder 22, brake hydraulic chambers 26 and 27 are respectively defined on the front side in the operation direction of the pistons 21 and 23, and the brake hydraulic chambers 26 and 27 are connected to the wheel (not shown) via the pipe 4. It is connected to the cylinder. Reservoir passages 28 and 29 are opened in the brake fluid pressure chambers 26 and 27, respectively.
The openings of the brake fluid pressure chambers 9 and 9 are opened when the respective pistons 21 and 23 are located at the non-operating positions, and communicate with the brake fluid pressure chambers 26 and 27, respectively. On the other hand, when the pistons 21 and 23 are advanced from the inoperative position, the pistons 21 and 23 are closed by the pistons 21 and 23.

Further, as shown in FIG. 1, after the two reservoir passages 28 and 29 are combined into one reservoir passage 30, a cylinder device 33 and a reservoir having the same configuration as a conventionally known single master cylinder are formed. Passage 3
4 communicates with the reservoir 35. This cylinder
The device 33 generates hydraulic pressure together with the actuator 45 described later.
Make up the device. As shown in an enlarged manner in FIG. 3 , the cylinder device 33 includes a cylinder 3
6 and a pressure chamber 3 formed in the cylinder 36 by the piston 37.
The pressure chamber 38 is connected to the reservoir passage 30 from the tandem master cylinder 3. A reservoir passage 34 connected to the reservoir 35 is connected to the pressure chamber 38. The opening of the reservoir passage 34 into the pressure chamber 38 is formed by the piston 37 having a spring 3
9 open when held in the inoperative position and close when the piston 37 is advanced from the inactive position against the spring 39.

As shown in FIG. 1, the reservoir passage 30 for communicating the pressure chamber 38 of the cylinder device 33 with the brake fluid pressure chambers 26 and 27 of the master cylinder 3 is provided with a bypass passage connected to the reservoir passage 30. The check valve 42 communicates with the reservoir 35 via a check valve 41 provided in the bypass passage 41, and the check valve 42 allows only the flow of the brake fluid from the reservoir 35 to the reservoir passage 30. ing. Therefore, even if the piston 37 of the cylinder device 33 is advanced and the reservoir passage 34 is closed, the bypass passage 4
1. The brake hydraulic chambers 26, 27 of the master cylinder 3 via the check valve 42 and the reservoir passages 30, 29, 28
The brake fluid can be replenished. Alternatively, even when the reservoir passage 34 is closed and the pistons 21 and 23 of the tandem master cylinder 3 are advanced and the reservoir passages 28 and 29 are closed,
The brake fluid can be replenished from the reservoir 35 to the pressure chamber 38 of the cylinder device 33 via the bypass passage 41, the check valve 42, and the reservoir passage 30.

Next, the piston 3 of the cylinder device 33
An actuator 45 having the same configuration as that of the negative pressure type brake booster is linked to 7. As shown in an enlarged view in FIG. 3, the actuator 45 includes a power piston 47 slidably provided in a shell 46, a power piston 47 attached to the back of the power piston 47, a front side in a pressure chamber 48, and a rear side. A diaphragm 50 that partitions the side into an atmospheric pressure chamber 49, and the atmospheric pressure chamber 49 is always in communication with the atmosphere via a filter 51 provided in the shell 46. At this time,
The right end face of the power piston 47 is a shell 4 when not in operation.
6, the slit 52 is formed in the right end face of the power piston 47 so that the atmospheric pressure chamber 49 is formed.
Make sure that they communicate with the atmosphere. On the other hand, the pressure chamber 48 is connected to the above-described negative pressure source 18 via a conduit 54, an electromagnetic flow path switching valve 55, a conduit 56, a regulator 57, and a conduit 58, as shown in FIG. In addition, the electromagnetic flow path switching valve 55 is normally deenergized to introduce the atmosphere into the pressure chamber 48, whereby the actuator 45 can be deactivated. On the other hand, when the flow path switching valve 55 is excited by the control device 59, its flow path is switched so that a negative pressure can be introduced into the pressure chamber 48 to operate the actuator 45. Has become. That is, if the atmospheric pressure is introduced into the pressure chamber 48 during the non-operation, no pressure difference occurs between the front and the rear of the power piston 47. Therefore, the power piston 47 is returned to the non-operation position by the return spring 60 as shown in FIG. Will be retained. On the other hand,
When a negative pressure is introduced into the pressure chamber 48, a pressure difference can be generated before and after the power piston 47, so that the power piston 47 can be advanced against the return spring 60. Further, a base of an output shaft 62 is linked to the power piston 47 via an elastic body 61, and a distal end of the output shaft 62 is protruded to the outside of the shell 46 via a seal member 63, and Of the piston 37. Although the elastic body 61 is essentially unnecessary, the provision of the elastic body 61 allows the degree of freedom between the power piston 47 and the output shaft 62 to smoothly press the piston 37 of the cylinder device 33. Can be.

Further, as shown in an enlarged view in FIG. 4, the regulator 57 has a cylindrical piston 67 provided in a housing 66 so as to be movable up and down. The upper end of the cylindrical piston 67 is an annular first valve seat 67a, and the outer periphery of the upper end of the plunger 68 is an annular second valve seat 68a. Above the cylindrical piston 67 and the plunger 68, a substantially cylindrical valve body 69 seated on the first valve seat 67a and the second valve seat 68a is provided. The cylindrical piston 67 is held at a lower end position by a spring 70, and the plunger 68 is held at a lower end position by a spring 71. In this non-operating state, the second valve seat 68a of the plunger 68 is Is located slightly lower than the first valve seat 67a of the
2, the first valve seat 67a is seated. A diaphragm 73 is stretched between the cylindrical piston 67 and the housing 66, thereby forming a pressure chamber 74 above the diaphragm 73 in the housing 66 and an atmospheric pressure chamber 75 below the diaphragm 73. are doing. Lower atmospheric pressure chamber 7
5 is always in communication with the atmosphere, but the upper pressure chamber 74 is connected to the flow path switching valve 55 through the above-mentioned conduit 56, and the pressure chamber 74 is formed in the radial direction formed in the cylindrical piston 67. It communicates with the axial passage 77 between the cylindrical piston 67 and the plunger 68 via the passage 76. Therefore, the axial passage 77 opens between the seat portion between the first valve seat 67a and the valve body 69 and the seat portion between the second valve seat 68a and the valve body 69. On the other hand, the radially outer side of the seat portion between the first valve seat 67a and the valve body 69 communicates with the negative pressure source 18 through the conduit 58, and the second valve seat 68a and the valve body 69 The inside of the seat portion in the radial direction is communicated with the atmosphere. Further, the housing 6
A servomotor 79 such as a stepping motor for raising and lowering the plunger 68 via a screw mechanism 78 is attached to 6. The servomotor 79 is controlled by the controller 59 to move the plunger 68 up and down to a predetermined height position. You can do it.

Therefore, when the regulator 57 is in the non-operating state shown in FIG.
8 is located at the lower end, the valve body 69 is seated on the first valve seat 67a, and is separated from the second valve seat 68a, while the negative pressure of the negative pressure source 18 communicated via the conduit 58. Is closed at the portion by the seating of the valve body 69 and the first valve seat 67a. On the other hand, the atmosphere on the inner peripheral side of the second valve seat 68a passes through the axial passage 77, the radial passage 76, and the pressure. Room 7
4 and a conduit 56 to a flow path switching valve 55. From this state, the servo motor 7 is
When the plunger 68 is raised through the valve 9, the valve body 69 is seated on the second valve seat 68 a of the plunger 68 to cut off the communication between the axial passage 77 and the atmosphere. The first valve seat 67a is separated from the first valve seat 67a. As a result, when a negative pressure from the negative pressure source 18 is introduced into the axial passage 77, the negative pressure is applied to the radial passage 7.
6. Flow path switching valve 55 via pressure chamber 74 and conduit 56
Will be supplied. When the negative pressure is introduced into the pressure chamber 74 in this manner, the cylindrical piston 67 is raised against the spring 70 due to the pressure difference between the atmospheric pressure chamber 75 and the cylindrical piston 67. Of the first valve seat 67a is integrally raised, so that the valve body 69 is attached to the first valve seat 67a.
To shut off the communication between the negative pressure source 18 and the axial passage 77. In this state, the biasing force for raising the cylindrical piston 68 due to the pressure difference between the pressure chamber 74 and the atmospheric pressure chamber 75 and the biasing force for the spring 70 to push down the cylindrical piston 68 are balanced. Therefore, if the elevation position of the plunger 68 is adjusted by the servo motor 79, the pressure difference between the pressure chamber 74 and the atmospheric pressure chamber 75, that is, the magnitude of the negative pressure in the pressure chamber 74 is adjusted accordingly. be able to. Therefore, this allows the flow path switching valve 5
5, the magnitude of the negative pressure supplied to the pressure chamber 48 of the actuator 45 can be adjusted.
Numeral 9 is adapted to receive a feedback signal from a pressure sensor 80 (FIG. 1) provided in the conduit 54.

Further, in FIG. 1, a plurality of sensors 81 are connected to the control device 59 for detecting the vehicle speed, the presence or absence of depression of an accelerator pedal, and the like. It is possible to detect whether or not the operating condition of the device is satisfied. In addition, a relay 82 having a normally closed contact is provided in an electric circuit connecting the control device 59 and the electromagnetic flow path switching valve 55, and the relay 82 detects that the brake pedal 1 is depressed. The brake switch 83 is connected in series. Therefore, when the brake pedal 1 is depressed and the brake switch 83 is closed,
When the relay 82 is opened and the flow path switching valve 55 is deactivated, the air is introduced into the pressure chamber 48 of the actuator 45 when the flow path switching valve 55 is deactivated, so that when the brake pedal 1 is depressed, Can always stop the operation of the actuator 45. Further, a signal from a release switch 84 operated by the driver can be input to the control device 59. When the release switch 84 is manually turned on, the control device 59 operates the automatic brake device. Even if the condition is satisfied, the electromagnetic flow path switching valve 55 is deenergized and the operation of the actuator 45 is stopped.

In the above configuration, when the automatic brake device is not operated, the flow path switching valve 55 introduces the atmosphere into the pressure chamber 48 of the actuator 45. In this state, the power piston 47 is returned to the non-operating position by the return spring 60. , The piston 37 of the cylinder device 33 is also held at the inoperative position. Therefore, the pressure chamber 38 in the cylinder 36 communicates with the reservoir 35 so that the internal pressure is kept at zero. On the other hand, in a state where the depression of the brake pedal 1 is released, the brake booster 2 and the master cylinder 3 are in a non-operation state, respectively.
Therefore, the brake hydraulic chamber 26 of the master cylinder 3
Since 27 communicates with the pressure chamber 38 of the cylinder device 33 through the reservoir passages 28, 29, 30, the pressure in the brake fluid pressure chambers 26, 27 is also kept at zero, and the braking action is released. When the brake pedal 1 is depressed from this state, it is apparent that the same operation as that of a conventional general brake device is performed.

Next, when the brake pedal 1 is not depressed and the automatic brake device is not operated, the control device 59 determines that the operating condition of the automatic brake device is satisfied by the signal input from the sensor 81. In this case, the control device 59 excites the flow path switching valve 55 to switch the circuit, and the regulator 57
To control the magnitude of the negative pressure to a required level. Then, the negative pressure controlled to the required magnitude by the regulator 57 is supplied to the pressure chamber 48 of the actuator 45 via the flow path switching valve 55, thereby generating a pressure difference before and after the power piston 47. Then, the power piston 47 is advanced, and the piston 37 of the cylinder device 33 is advanced via the output shaft 62. When the piston 37 of the cylinder device 33 is advanced, the reservoir passage 34 connected to the reservoir 35 is closed, so that a brake pressure is generated in the pressure chamber 38, and the brake pressure is applied to the reservoir passages 30, 28, 29. The brake fluid is introduced into the brake fluid pressure chambers 26 and 27 of the tandem master cylinder 3 via the pipe, and is further supplied to a wheel cylinder (not shown) via the pipe 4 so that the braking action is performed without depressing the brake pedal 1. The braking force at this time can be controlled to a required magnitude by controlling the magnitude of the negative pressure by the regulator 57. During the automatic braking operation, the brake pedal 1
Is depressed, as described above, the brake switch 83 is closed and the relay 82 is opened, whereby the flow path switching valve 55 is switched to the non-operating state and the actuator 4
Since the atmosphere is introduced into the pressure chamber 48 of the fifth embodiment, the power piston 47 is returned to the non-operating position by the return spring 60. At this time, the pistons 21 and 23 of the tandem master cylinder 3 move forward to close the reservoir passages 28 and 29. However, in the pressure chamber 38 of the cylinder device 33, the bypass passage 41, Since the brake fluid is replenished through the check valve 42 and the reservoir passage 30, the actuator 45 can smoothly return to the original non-operating state.

FIG. 5 shows a second embodiment of the present invention. In the first embodiment, the magnitude of the negative pressure supplied to the pressure chamber 48 of the actuator 45 is adjusted by the regulator 57. In this embodiment, the flow path switching valve 155 itself corresponding to the flow path switching valve 55 of the first embodiment has a pressure control function.
Can be omitted. That is, the flow path switching valve 155 of this embodiment includes a first opening / closing valve 155A and a second opening / closing valve 155B that are controlled to be opened / closed by the control device 59, and these opening / closing valves are connected in series with each other. Passage 1 connecting both on-off valves 155A and 155B
87 is connected to the pressure chamber 4 of the actuator 45 through the conduit 154.
8 is connected. The first on-off valve 155A communicates with the atmosphere, the second on-off valve 155B communicates with the negative pressure source 18, and a pressure sensor 188 for detecting the internal pressure is provided in the passage 187. Is input to the control device 59. Other configurations are the same as those of the first embodiment.

In this embodiment, the control device 59 causes the first on-off valve 155A to open when not operating, and the second on-off valve 15
5B is closed. In this state, the atmosphere is the first on-off valve 1
Actuator 45 is held inactive since it is introduced into pressure chamber 48 of actuator 45 via 55A, passage 187 and conduit 154. When performing the automatic braking action from this state, the control device 59 opens and closes the first on-off valve 155A,
Since the second on-off valve 155B is opened and closed at a timing opposite to that of the first on-off valve 155A, a negative pressure from the second on-off valve 155B is set in the pressure chamber 48 of the actuator 45.
Atmospheric pressure is alternately introduced from the first on-off valve 155A. Therefore, while detecting the pressure by the pressure sensor 188, the opening / closing time of the first opening / closing valve 155A and the opening / closing time of the second opening / closing valve 155B are appropriately changed and adjusted, whereby the pressure chamber 4 of the actuator 45 is adjusted.
The magnitude of the negative pressure introduced into the chamber 8 can be controlled to a required level.

FIG. 6 shows a third embodiment of the present invention. In this embodiment, a single-type cylinder device 33 having one pressure chamber 38 used in the above embodiment is used as a hydraulic pressure generating device. On the other hand, a tandem type cylinder device 233 having two pressure chambers in series is used, and a servo motor 245 such as a stepping motor is used as an actuator for operating the cylinder device 233. That is, the cylinder device 233 is
6 are provided with two pistons 237A, 237B, each of which is held in a non-operating position by springs 239A, 239B, respectively. A pressure chamber 238 is provided in front of each piston 237A, 237B.
A and 238B are formed, and each pressure chamber communicates with the common reservoir 235 via the reservoir passages 234A and 234B. These reservoir passages 234A, 234B
The openings to the pressure chambers 238A, 238B are opened when the respective pistons 237A, 237B are located at the non-operation positions, and communicate with the pressure chambers 238A, 238B, respectively. Pistons 237A, 23
When 7B is advanced from the inoperative position, each piston 23
7A, 237B.
Further, the pressure chambers 238A and 238B are connected to the brake hydraulic chambers 26 and 27 of the tandem master cylinder 3 via conduits 230A and 230B, respectively (see FIG. 2).
Is communicated with. The servo motor 245 is attached to the housing 236 of the cylinder device 233, and the rotation shaft 245A of the servo motor 245 is linked to one piston 237A via a screw mechanism 290. The servomotor 245 is controlled by the control device 59 so as to move the piston 237A forward and backward. Other configurations are the same as those of the first embodiment.

According to the present embodiment, if the control device 59 controls the servomotor 245 to control the amount of advance of the piston 237A, the necessary hydraulic pressure can be reduced to the pressure chambers 238A, 238.
B can be generated. Therefore, also in this embodiment, the same operation and effect as those of the first embodiment can be obtained.

FIG. 7 shows a fourth embodiment of the present invention. In this embodiment, a cylinder device 333 corresponding to the cylinder device 33 of the first embodiment is used as a hydraulic pressure generating device.
In addition, an actuator 345 having substantially the same configuration as the hydraulic cylinder device is interlocked. The actuator 345 is connected to the cylinder 336 of the cylinder device 333.
And a housing 346 integrally formed with the power piston 347. The power piston 347 is slidably fitted in the housing 346 while maintaining liquid tightness. The above power piston 3
A pressure chamber 348 is formed on the rear side in the operation direction of 47, and an atmospheric pressure chamber 349 communicating with the atmosphere through an opening 346a formed in the housing 346 is formed on the front side. The pressure chamber 348 communicates with the discharge side of the pump 393 via a supply passage 392, and communicates with a reservoir 396 of the pump 393 via a discharge passage 394 and a flow control means 395 having a variable orifice.
The reservoir 396 and the suction side of the pump 393 communicate with each other through a passage 397.
The oil discharged from 93 is supplied to supply passage 392 and pressure chamber 34.
8. The liquid is returned to the reservoir 396 via the discharge passage 394 and the flow control means 395. The flow rate adjusting means 395 is configured such that the flow area of the variable orifice is controlled by the control device 59, and the pressure chamber 34 is controlled by controlling the flow area of the variable orifice.
8 can be adjusted.
Since the flow rate adjusting means 395 having such a configuration is conventionally known, the description of the specific configuration will be omitted. Further, the pump 393 may be also used as a power steering pump, or may be a dedicated pump. When the power piston 347 is not operated, the power piston 347 is held at the illustrated position by a spring 398. In this state, the piston 337 of the cylinder device 333 linked to the power piston 347 is also held at the illustrated non-operating position. A pressure chamber 338 formed on the left side of 337 is connected to a reservoir 33 through a reservoir passage 334.
5 is connected. On the other hand, the pressure chamber 338 communicates with the tandem master cylinder 3 via the reservoir passages 30, 29, and 28 as in the first embodiment. The other configuration is the same as that of the first embodiment, and the present embodiment can provide the same operation and effects as those of the first embodiment.

[0021]

As described above, according to the present invention, at the time of automatic braking, the actuator advances the piston of the cylinder device to generate pressure, and the pressure is applied to the wheel cylinder via the brake fluid pressure chamber of the master cylinder. By supplying the brake, the braking action can be automatically performed. Even if the cylinder device or the master cylinder breaks down, the brake system on the master cylinder side is not affected at all, and if the brake pedal is depressed, brake hydraulic pressure is generated in the brake hydraulic chamber of the master cylinder. As a result, a braking action can be performed.

[Brief description of the drawings]

FIG. 1 is a partial sectional system diagram showing a first embodiment of the present invention.

FIG. 2 is an enlarged sectional view showing a brake booster 2 and a tandem master cylinder 3 of FIG. 1 in an enlarged manner.

FIG. 3 is an enlarged sectional view showing a cylinder device 33 and an actuator 45 of FIG. 1 in an enlarged manner.

FIG. 4 is an enlarged sectional view showing a regulator 57 of FIG. 1 in an enlarged manner.

FIG. 5 is a system diagram of a main part showing a second embodiment of the present invention.

FIG. 6 is a partial sectional system diagram showing a third embodiment of the present invention.

FIG. 7 is a partial sectional system diagram showing a fourth embodiment of the present invention.

[Description of sign]

DESCRIPTION OF SYMBOLS 1 ... Brake pedal 2 ... Negative pressure type brake booster 3 ... Tandem master cylinder 21, 23 ... Piston 22 ... Cylinder 26, 27 ... Brake fluid pressure chamber 28, 29, 30, 34, 230A, 230B, 234
A, 234B, 334 ... reservoir passages 33, 233, 3
33 ... Cylinder devices 35, 235, 335 ... Reservoirs 36, 236, 3
36: cylinder 37, 237A, 237B, 337: piston 38, 338: pressure chamber 45, 245, 345
... actuators 47, 347 ... power pistons 48, 348 ... pressure chambers 49, 349 ... atmospheric pressure chambers 55, 155 ... flow path switching valves 57 ... regulators 59 ... control devices 66 ... housings 67 ... cylindrical pistons 67a ... first valve seats. 68 plunger 68a second valve seat 69 valve body 73 diaphragm 74 pressure chamber 75 atmospheric pressure chamber 76, 77 passage 79 servo motor 83 brake switch 84 release switch

Continuation of front page (56) References JP-A-3-86663 (JP, A) JP-A-4-362453 (JP, A) Table 9-9-511967 (JP, A) (58) Fields surveyed (Int .Cl. ⁷ , DB name) B60T 13/12

Claims (9)

(57) [Claims] 1. A brake according to a depression force of a brake pedal.
Generates hydraulic pressure and applies the brake hydraulic pressure to the wheel cylinder.
Master cylinder that supplies the
A brake device for generating the brake fluid pressure of the master cylinder.
When the brake pedal is not operated,
A reservoir through which the brake hydraulic chamber communicates with the reservoir
A hydraulic pressure generator for supplying hydraulic pressure via
An automatic brake device comprising a control device for controlling a raw device . Wherein said hydraulic pressure generating device to generate the liquid pressure
Cylinder and a differential pressure between atmospheric pressure and negative pressure.
Actuating the piston of the cylinder device by operating
And a motor, the controller, the atmospheric pressure and the negative pressure in the actuator selection
The fluid pressure is controlled by controlling a flow path switching valve to be selectively introduced.
Automatic braking device according to claim 1, characterized in that that. 3. The flow path switching valve is connected to a negative pressure source via a regulator.
A servo motor controlled by the
The negative pressure of the negative pressure source is adjusted by the operation of the
The automatic brake device according to claim 2, wherein a negative pressure is supplied to the switching valve . 4. The flow path switching valve controls the atmospheric pressure of the activator.
A first opening / closing valve for supplying a negative pressure to the actuator.
The automatic brake device according to claim 2, wherein the automatic brake device is configured by a second opening / closing valve that supplies to the motor . 5. The hydraulic pressure generator generates the hydraulic pressure.
Operating the cylinder device and the piston of this cylinder device
And a servo motor for controlling the servo motor.
The automatic brake device according to claim 1, wherein the hydraulic pressure is controlled by controlling a servo motor . 6. The hydraulic pressure generator generates the hydraulic pressure.
Cylinder device that operates by hydraulic pressure
Actuator that operates the piston of
A pump for supplying hydraulic pressure to the eta,
Is connected to the discharge passage that returns from the actuator to the pump.
Automatic braking device according to claim 1, characterized in <br/> controlling on SL liquid pressure obtained flow prepared means control to the to provided. 7. The system according to claim 7, wherein said hydraulic pressure generating device is
In the middle of the reservoir passage communicating with the brake pressure chamber,
A pass passage is provided, and the bypass passage is the reservoir passage.
And the reservoir and the bypass passage.
Check valve that allows only the flow of brake fluid to the brake fluid chamber
Automatic braking device according to any one of claims 1 to 6, characterized in that provided. 8. A brake switch for detecting that a brake pedal is depressed, and when the brake pedal is depressed, the control device activates the hydraulic pressure generating device.
The automatic brake device according to claim 1, wherein the automatic brake device is stopped . 9. A control device comprising a release switch operated by a driver.
The automatic brake device according to any one of claims 1 to 8, wherein the operation of the pressure generating device is stopped .