JPS61157458A - Automobile brake system - Google Patents

Abstract

PURPOSE:To surely operate a brake even upon occurrence of a trouble, by connecting a pressure source to a pressure chamber in a booster through a dual system hydraulic circuit, and by exclusively selecting the communication or isolation of several systems upon normal operation of a computer or upon abnormal operation of the computer. CONSTITUTION:A reservoir chamber 24 in a brake force transmission cylinder 8 is connected to an accumulator 28 and a hydraulic pump 29 through a hydraulic circuit 31 having a control valve 27. Further, the accumulator 28 is connected to a reservoir chamber in a depressing force cylinder 10 through a hydraulic circuit 57 while the reservoir chamber is connected to a pressure regulating chamber (which is not shown) through a depressing force change-over valve. Further, this pressure regulating chamber is connected to the reservoir chamber 24 through a hydraulic circuit 63 having a change-over valve 62. These valves 27, 62 are controlled by a computer 7. Normally, the valve 27 is opened but the valve 62 is closed, and therefore, the pressure is fed from the circuit 31. When the computer 7 is abnormal, the valves 27, 62 are changed over so that the pressure is fed from the circuit 63.

Description

[Detailed Description of the Invention] <Industrial Application Field> The disclosed technology enables the braking of automobiles to be applied regardless of heavy loading, fluctuations in the brake mechanism, troubles in the electrical system, etc.
It belongs to the technical field of systems that can demonstrate stable control performance.

In this invention, a brake pedal provided on the driver's seat of an automobile is linked to a master cylinder, and a control valve for a hydraulic circuit connected to the master cylinder is connected to a vehicle speed sensor and a depression force provided on the brake pedal. This invention relates to a brake system that is optimally controlled by a computer based on data from a detection mechanism, and in particular,
Regarding the braking force transmission system for the power piston that transmits braking force from the master cylinder to the front and rear wheel brakes, there is one L attached to the hydraulic circuit.
+ A system that performs hydraulic control using a control valve and uses only hydraulic pressure, and a system that uses hydraulic pressure alone through a switching pulp in the case of computer failure or electrical system trouble, or when the set deceleration is not satisfied. This invention relates to a brake system for an automatic east car, in which only hydraulic pressure is controlled, and the system operated by the hydraulic pressure is also divided into two systems, and the two systems are automatically selected mutually and exclusively by a computer. Pa that is.

<Prior art> - As is well known, automobiles have a brake system as one of the safety devices, but the brake system has the basic functions of deceleration and stopping. We have reached a satisfactory level, and in order to respond to the diversification of usage patterns and further improve safety,
Research into anti-slip technologies using powerful boost braking and excessive braking led to the development and adoption of hydrobrake systems for the former and so-called anti-skid systems for the latter.

<Problems to be solved by the invention> However, in these already developed brake systems, the system itself has been fixed as a single setting system and researched and developed, so the number of occupants and carrying load of the vehicle cannot be adjusted. For example, changes in brake deceleration in response to changes in weight due to fluctuations in weight, and various decelerations that vary depending on the driver's physique, strength, habits, senses, etc. The deceleration may vary widely, such as not being able to obtain the expected deceleration even if you apply pedal force with a sense of controlled movement.
The actual braking that is achieved does not work as designed, and there is actually an imbalance in deceleration due to the widespread use of expressways and various changes in driving conditions over time on rough roads. Also, changes in deceleration due to changes in the friction coefficient of the friction material of the brake mechanism part, for example, the brake pad,
Furthermore, due to changes in shoe clearance, etc., the deceleration performance is not constant and cannot be stabilized, and the actual background of this situation has been brought into sharp focus, such as a delay in brake operation and the like resulting in dangerous situations.

Nevertheless, as mentioned above, the mechanical part of the brake system installed in actual vehicles adopts an average target design or a fixed mechanism based on a theoretical standard design.
It has the disadvantage of not being able to accommodate a variety of different deceleration rates, and it is an ergonomic demand that the driver expects the deceleration to correspond to the force applied to the brake pedal when driving the vehicle while actually operating the vehicle. There was also the difficulty of not being able to respond immediately.

In addition, the use of microcomputer-based electronic control systems such as the above-mentioned anti-skid system inevitably causes troubles in the electronic mechanism due to radio wave interference, and is unavoidable for a long period of time. IC of parts
A high-precision brake system may not be able to perform its initial function due to troubles such as circuit shorts, so it is necessary to convert the braking mode so that the brake can reliably perform its braking function with just the master cylinder's hydraulic pressure based on the basic pedal force. There was also the drawback that it was not always what we expected.

Therefore, a brake system that makes full use of such extremely high-tech mechatronic technology can respond flexibly and quickly to various conditions, and can always achieve safe braking, which is the basic first condition of a brake system, and optimal control that can be added on top of that. Therefore, from the user's perspective, there was a disadvantage in that there were concerns that there were some parts that were not cost-effective.

To deal with this, for example, Japanese Patent Application Laid-Open No. 58-126245
Like the invention described in the publication, technology has been developed that guarantees boost braking without applying brake reaction force even when trouble occurs, but even when trouble does not occur, the start-up timing and desired reduction There was a problem in which it was not possible to respond smoothly when the speed was insufficient, making it difficult to tell when a problem was occurring.
- Also, although an anti-trouble mechanism similar to the above-mentioned one has been developed, such as the invention described in Japanese Patent Application Laid-Open No. 58-84652, there remains the inconvenience that smooth switching between the two systems of the hydraulic circuit is not possible.

The purpose of the present invention is to provide a system that is independent of changes in the load weight of the vehicle body based on the above-mentioned prior art, and is independent of road conditions.
Furthermore, #l of the brake! Regardless of wear of the friction material or changes in shoe clearance, the basic safety braking function is maintained using only the optimum pedal force even in the event of system trouble, and the driver's safety is maintained regardless of the conditions of the vehicle in question. Even when the braking mode is automatically changed according to the applied pedal force, there is no shock and the expected deceleration is obtained smoothly, and a guarantee function is provided between modes to ensure the full performance of the advanced braking mechanism. The purpose of the present invention is to provide an excellent automobile braking system that will benefit the field of safety technology application in the automobile industry by making the most of the advantages of the present invention. .

Means and operation for solving the above-mentioned problems> In accordance with the above-mentioned object, the structure of the present invention, which is summarized in the above-mentioned claims, is such that the equipped brake system operates normally in order to solve the above-mentioned problems. When braking while driving in
When a desired pedal force is applied to the brake pedal, a pedal force detection mechanism linked to the brake pedal detects the applied pedal force and inputs the detection signal to the computer;
The vehicle speed sensors on the front and rear wheels detect the highest vehicle speed at any position and input the detection signal to the computer, so the computer calculates the reference vehicle speed at that speed and applies the detected signal to the computer. The optimal deceleration according to the pedal force is calculated and a predetermined control signal is sent to one control valve in the hydraulic circuit to operate the spool valve of the pedal force cylinder, and the hydraulic pressure from the control valve in the hydraulic circuit is transferred to the power piston of the master cylinder. The master cylinder applies hydraulically assisted braking pressure to each of the front and V-wheel brakes to provide a predetermined deceleration and brake, and the momentary deceleration state is Feedback is sent to the computer via the heavy speed sensor, and when the deceleration exceeds the set deceleration, the control valve is closed and the power piston of the master cylinder applies hydraulic pressure to the front and rear wheel brakes. The braking pressure of the booster is released, and this repetitive control automatically decelerates as set. During this time, the pedal force applied to the brake pedal is only affected by the resistance of the feeling spring installed in the booster, and the computer To ensure that a linear input of the pedal force is transmitted to ensure the expected deceleration according to the pedal force, there will be no radio interference to the brake system's computer, or any damage to the electronic components. If vibrations that are repeatedly applied to the wiring etc. cause short circuits and malfunction, or if there is insufficient hydraulic pressure from the control valve due to problems caused by lack of familiarity with a new car, etc., the computer will shut off the problem. In a hydraulic circuit in which the above control valve and other switching valves are set, the former is automatically closed and the latter opened, and the main bushing rod installed on the brake pedal controls the spool piston to switch the above. Hydraulic pressure from the valve is applied to the power piston to ensure smooth shifting without causing shock during mode switching, and to apply hydraulic pressure to the front, rear, and rear wheel brakes. The control force applied to the piston operates linearly with the feeling spring, and the power piston applies hydraulic pressure to the front, rear, and rear wheels in the same manner as a normal hydraulic brake system, mechanically converting the force into the pedal force. Therefore, in the event of a problem such as a failure in the hydraulic system, the main bushing rod will be set to zero hydraulic pressure for the two systems of fully automatic and semi-automatic braking mentioned above. The sub-button rod does not move, and only the sub-button rod pushes the power piston of the master cylinder, so the front,
and technical technology that ensures braking that can exert the minimum safety function as a brake by applying normal hydraulic braking force without boost to one or both wheels. The measures were taken.

<Embodiment - Configuration> Next, one embodiment of the present invention will be described below based on the drawings.

In FIG. 2, reference numeral 1 denotes an automobile brake system, which constitutes the gist of the present invention, in which a booster 2 is linked to a brake pedal 5 via a main bushing rod 3 and a sub bushing rod 4. .

In addition, the vehicle speed sensors 6, 6, etc. provided for the front and left and right axles of A7 are electrically connected to the computer 7, and input their detected vehicle speeds, and select the fastest one. It is designed to measure the vehicle speed.

As shown in detail in FIG. 1, the booster 2 includes a braking force transmission cylinder 8 on the base side and a master cylinder 9 of the same mechanism as in the conventional mode, which is provided integrally in front of the braking force transmission cylinder 8. , consists of a pedal force cylinder 10 that is integrally provided on the lower side, and the master cylinder 9 is connected to the control piston 1.
1 forms a front hydraulic chamber 13 in which a return spring 12 is interposed in its front part, which is connected to a reservoir chamber 14 connected to a reservoir tank (not shown), and also connected to a front wheel brake 15, and is also formed in the rear part. The rear hydraulic chamber 16 communicates with a reservoir chamber 11 which is also connected to a reservoir tank (not shown), and as shown in FIG.
It is connected to a rear wheel brake 19 via a provisioning valve 18.

Further, as described above, the braking force transmission cylinder 8, which is provided integrally with and extending after the master cylinder 9, has a power piston 21 with an area D1, which is provided on the control piston 11 via a return spring 20, on the front and rear sides thereof. A reservoir chamber 22 and a pressurizing chamber 23 are formed between the reservoir chambers 22 and 23, respectively. 11 and 24.

Further, a sub-button rod 4 is mounted on the rear end of the power piston 21 via a seal 25, and the rear end has a set length with respect to the upper part of the brake pedal 5, as shown in FIG. A rod receiver 26 having a U-shaped cross section and forming a slight play is loosely inserted and connected. - Therefore, the reservoir chamber 24 of the braking force transmission cylinder 8 is
As shown in FIG. 2, one three-position control valve 27,
It is connected to a hydraulic circuit 31 having an accumulator 28, a hydraulic pump 29, and an oil tank 30.

The function of the control pulp 21 is that of the power piston 12.
1 is exclusively used for hydraulic assist doubler control, and is electrically connected to the computer 7, and is equipped with an attached diagram in case of unforeseen circumstances such as radio wave interference or short-circuiting of the IC or printed circuit board of the computer 1 due to automobile vibration. It is always closed by a spring that does not control the power piston 21.

Further, on the lower side of the braking force transmission cylinder 8, as shown in FIG. and the pressurizing chamber 35 formed between the rear side and the casing and the braking force transmission cylinder 8.
A boat 36 is communicated between the reservoir chamber 22 formed in the control piston 32, and a port 37 communicating with the rear pressurizing chamber 23 of the braking force transmission cylinder 8 is provided on the outside of the control piston 32. A neck-shaped front communication portion 39 of the control valve 32 communicates with a front chamber formed through a port (not shown) through a cup-shaped seal lip 38 having a U-shaped cross section.

Further, a pedal force piston 40 is connected to the pedal force cylinder 10, which is integrally formed below the braking force transmission cylinder 8 through the casing of the control valve 32, and is moved forward via a feeling spring 41 with a set load. It is slidably inserted and connected to the main bushing rod 3, and a control piston 42 is provided at the front of the main bushing rod 3 via a pressurizing chamber 44 having an elastic spring 43.

The oil in the pressurized chamber 44 is connected to the neck-shaped communication portion 39 of the control valve 32 via the boat 45, and is connected to the cup-shaped seal through the forward movement of the control valve 32. The deflection of the lip 38 communicates with the port 36, and the reservoir chamber 22 at the front of the ill power transmission cylinder 8 communicates with the reservoir v1γ.

The reservoir chamber 46 of the front pressurizing chamber 44 of the pedal force piston 40 is connected to an appropriate hydraulic pressure sensor 47 as a pedal force detection mechanism, as shown in FIG.

The hydraulic pressure sensor 41 is electrically connected to the computer 1 and inputs the detected pedal force signal.

Further, a return spring 48 is interposed at the front end of the control piston 21 with respect to the casing to open and close the boat 50 with respect to the reservoir chamber 49, and also to cut off communication with the port 52 of the reservoir chamber 51. A spool piston 51 having an area D2, which has a boat 53 in the radial direction that can be freely moved, and a boat 56 in the longitudinal direction that communicates with the pressure regulating chamber 55 via a boat 54 in the radial direction, can slide back and forth. It is provided.

The reservoir chamber 51 has the above-mentioned 1. A hydraulic circuit 59 to which a hydraulic circuit 57 branching from the II control valve 21 is connected, and a check valve 58 is interposed in the hydraulic circuit 31 from the pressure regulating chamber 55 to the reservoir chamber 24 of the pressurizing chamber 23;
is connected.

A feedback circuit 50 to the oil tank 30 and a feedback circuit 61 to the control valve 27 are connected from the reservoir chamber 49.

A two-way valve 62 as a switching valve electrically connected to the computer is connected from the hydraulic circuit 59 to the hydraulic circuit 31.
A hydraulic circuit 63 having the following functions is interposed in parallel.

The opening/closing 1111 control of the control valve 27 and the switching valve 62 is reversed, and in the normal state, the former is open and the latter is closed or neutral, and when the deceleration is below the set deceleration or the computer is abnormal. , and in the event of a trouble such as an electrical system failure, the situation is reversed.

In this way, the control valve 27 and the switching valve 62 form two systems for applying hydraulically assisted boosting power to the power piston 21, the former being automatic and the superior being semi-automatic, and the computer 1 excludes both systems. Inside.

I am trying to automatically switch to .

Also, since the hydraulic circuits 58 and 63 are in parallel, the second
When the control valve 27 shown in the figure is open, hydraulic pressure is applied to the reservoir chamber 24 by opening the check pulp 58, whereas when the switching valve 62 is open, hydraulic pressure is applied from the switching valve 62 to the reservoir chamber 24. ing.

In addition, in the state shown in FIG. 2, the control valve 27 has a slow rise.
Then, oil pressure is applied to the reservoir chamber 24 from the check pulp 58, and in a normal state, oil pressure is applied to the reservoir chamber 24 from the control valve 27, and the control is automatically performed by the function of the check valve 58, and the control pulp 21 The servo ratio (D2/θ) 2 during operation is set relatively low to prevent oil from flowing back into the control valve 27 in the state shown in FIG.

<Embodiment - Effect> In the above-described configuration, when applying braking to a running automobile to decelerate or decelerate to a stop, the computer 7
is always the front and rear vehicle speed sensor 6.6...
The vehicle speed is detected, and the fastest vehicle speed of p% is measured at each time.

During the driving process, various loads such as people and cargo are applied to the vehicle, and the degree of wear of friction materials such as brake pads may vary depending on the type of vehicle, aging, etc. There are changes in shoe clearance, etc., and the potential conditions for braking are different.

Then, the driver intuitively grasps the braking situation and applies a pedal force to the brake pedal 5 in anticipation of a deceleration corresponding to the pedal force applied to the brake pedal 5 operated by the driver.

Therefore, in the normal state, that is, the state shown in FIG. 2 where there is no trouble or failure in the system, the pedal force applied to the brake pedal 5 is applied linearly against the set load of the feeling spring 41, that is, as it feels. , is applied to the pressurizing chamber 44 via the main bush rod 3, and is applied to the reservoir chamber 46.
The pedal force is detected by the hydraulic pressure sensor 41 of the pedal force detection mechanism and inputted to the computer 1, and the computer 7 then calculates the reference vehicle speed at the vehicle speed determined by the vehicle speed sensor 6, 6... and calculates the reference vehicle speed based on the pedal force. Calculate the optimal deceleration accordingly.

This relationship is shown in the graph of Figure 4', where the horizontal axis represents time t and the vertical axis represents vehicle speed S. The calculated vehicle speed corresponding to the set vehicle speed of graph C is the same as that of graph C'. It is shown as follows.

Therefore, the hydraulic pump 29 of the hydraulic circuit is connected to the oil tank 42.
A predetermined hydraulic pressure is supplied to the reservoir chamber of the corresponding braking force transmission cylinder 8 via the control valve 27 using the oil from the brake or the hydraulic pressure accumulated in the accumulator 28 .

However, in the initial operation of the brake pedal 5, the response of the hydraulic circuit 31 via the control valve 21 is slow and the rise is not quick, so the oil transmits hydraulic pressure to the hydraulic circuit 51 rather than to the hydraulic circuit 59.

At this time, the set load of the elastic spring 34 between the control valve 32 and the plug 33 and the boat 3 of the pressurizing chamber 23
1 is greater than the pressure in the pressure chamber 44 of the pedal force cylinder 10, the control valve 32 is pushed to the left in FIG. 1, shutting off the boats 36 and 45.
In order to seal the oil in the pressurizing chamber 44 of the pedal force cylinder 10 and maintain hydraulic rigidity, the pedal force applied from the main bushing rod 3 via the rookie pedal 5 is linear with the set load of the feeling spring 41. In response to this, the driver applies the expected resistance force to the brake pedal 5,
That is, it is possible to apply a braking force that causes deceleration.

In this case, although the drag force of the feeling spring 41 is a dummy force, it is intuitively perceived by the driver as a braking load.

Therefore, the pedal force applied by the driver to the brake pedal 5 is applied with a completely normal braking feeling, regardless of the change in the load or the unique changing situation of the car's brakes. .

On the other hand, no pedal force is applied to the sub-push port/rad 4 of the IIIfJ force transmission cylinder 8 for a while due to the predetermined play provided above the brake pedal 5 of the rod receiver 26 at its base end.

Therefore, the tread force piston 40 moves the spool piston 51 forward through the control piston 42 through the hydraulic pressure in the pressurizing chamber 44 against the return spring 48 at its tip, and as a result, the spool piston 51 moves forward into the reservoir chamber 49. The boat 53 and the boat 52 of the reservoir chamber 51 are connected to each other, so that the voltage is applied to the reservoir chamber 51. Hydraulic pressure from the hydraulic pump 29 is supplied to the reservoir chamber 51 and the boat 5 via the hydraulic circuit 5'9.
2.53, boat 28.37, pressure control room 55
As a result, the hydraulic pressure transmitted through the pressure regulating chamber 55 and the hydraulic circuit 59 opens the check pulse 5 158 and is transmitted from the reservoir chamber 24 to the pressurizing chamber 23, and is transmitted to the power piston chamber 55 and the hydraulic circuit 59. 21 is pressed and moves forward against the return springs 12 and 20, transmitting the hydraulic pressure from the reservoir chamber 14 of the front hydraulic chamber 13 to the front wheel brake 15, while transmitting the hydraulic pressure from the reservoir chamber 1γ of the hydraulic chamber 16 to the front wheel brake 15. Hydraulic pressure is applied to the 97 wheel brake 19 to operate the booster braking to provide the above-mentioned predetermined deceleration.

During this time, the tip of the spool piston 51 disconnects the boat 50 from the reservoir chamber 49.1. Therefore, the server ratio is (D2/DI)2.

As described above, since the 1iIJIII pulp 21 is in the open state, the hydraulic pressure does not flow backward, and the application of braking force to the power piston 21 is reliably maintained.

Since the mechanical servo ratio (D2/DI) 2 is set relatively low, the hydraulic pressure from the control valve 27 soon increases and becomes larger than the hydraulic circuit 59 side, so that the check valve 58 is closed. It closes and operates to transmit hydraulic pressure to the reservoir chamber 24.

Therefore, during this period, the check valve 58 causes a smooth transition, so no shock occurs.

Therefore, no depression force from the brake pedal 5 is applied to the sub-bush rod 4 as described above.

When the vehicle speed is reduced in this way, the vehicle speed sensor 8 detects the deceleration state and inputs it to the computer 7, and as shown in FIG. When the vehicle speed C' is reduced by a set speed relative to the vehicle speed C, a control signal is sent to the solenoid of the control valve 27 and connected to the middle chamber or rear end of the control valve 2T, which applies a braking force to the power piston 21. It operates to maintain or reduce the application. -□ Therefore, the oil pressure in the pressurizing chamber 23 is rapidly reduced, and as a result, the power piston 21 becomes neutral or retreats, and the deceleration decreases.

Therefore, due to the neutral posture of the control pulp 27, the reservoir chamber 2
4. The hydraulic pressure in the pressurizing chamber 23 is maintained at the hydraulic pressure at which the deceleration operation was performed immediately before, so that the pressure in the pressurizing chamber of the control valve 32 via the boat 31 is maintained, and the control valve 32 is still at the same level as above. maintain a forward posture,
Therefore, the pedal force applied to the brake pedal 5 is applied to the pedal force cylinder 10 to maintain a linear pedal force application state based on the set loads of the brake pedal 41.

When the computer 7 commanded to stop deceleration,
The control valve 21 has its rear chamber connected to the feedback circuit 61;
The oil that entered the reservoir chamber 61 is transferred to ports 52, 53, and 5.
6.5o to the reservoir chamber 49 and return to the oil tank 30 via the return circuit 60, the oil pressure in the pressurizing chamber 23 decreases, and therefore the power piston 21 retreats and The lower part 4 is also moved back via the return spring 12.20.

However, since the base end of the sub-bush rod 4 is loosely engaged with the brake pedal 5 via the Rondo receiver 26 which has some play, no interference with the brake pedal 5 occurs.

Therefore, as the power piston 21 moves backward, the hydraulic pressures in the front hydraulic chambers 13, 16 and the rear hydraulic chambers 16 are reduced, so that the front wheel brakes 15,
The braking applied to the rear wheel brake 19 is lost, the deceleration up to that point is lost, and the graph C of the vehicle speed set in Fig. 4
On the other hand, the graph C' of the decelerated vehicle speed is close to or exceeds this.

Meanwhile, the ζ vehicle speed sensors 6, 6... measure the vehicle speed in the deceleration or deceleration maintenance state and send it to the computer 7, and when the vehicle speed exceeds the set reference vehicle speed C for the deceleration state in FIG. The computer 7 commands deceleration again, and the command signal closes the control valve 27 or returns it from the neutral state to the open state, and connects the front chamber 48 to the hydraulic circuit 31, as described above. Therefore, as described above, hydraulic pressure is again applied to the pressurizing chamber 23 to apply a boost braking force to the power piston 21.

By repeating this process, the pressurized chamber 23
i, Il! The IJ pressure is maintained in the pressurizing chamber of the control valve 32 through the port 37, so that the pedal force applied to the brake pedal 5 is always maintained in a linear applied state due to the set load of the feeling spring 41 of the pedal force cylinder 10. Ru.

In order to constantly detect the actual vehicle speed by the vehicle speed sensor 6, 6, and send it to the computer 7, such an operation is performed as shown in FIG.
The control valve 27 opens and closes frequently in accordance with the frequency at which the graph C' of the vehicle speed during the actual deceleration dynamically approaches and separates, causing the power piston 21 to move relatively back and forth, thereby causing the brake The state of applying the pedal force to the pedal 5 is the feeling spring 41 of the cylinder 10.
Regardless of changes in the live load or changes in the brake pad or shoe clearance, braking is performed at the deceleration expected by the driver, which is set extremely linearly to the applied pedal force. will appear.

Therefore, the computer performs the control.7
However, as is well known, if the computer 7 is subjected to severe radio interference, its control function may malfunction or become inoperable, or the IC printed circuit board wiring of the computer 7, or If a short circuit or disconnection occurs in the wiring of the lead wire around the lead wire due to severe vibration over time during running, an appropriate operating signal will not be sent to each control valve 27, and therefore, as described above, There is a risk that the hydraulic servo brake control with increased boost will not be possible.

Furthermore, due to other unforeseen circumstances, there is a possibility that the set deceleration cannot be achieved with respect to the reference vehicle speed.

To deal with this, when a problem occurs in the electrical system, or even if the deceleration is lower than the set deceleration as mentioned above, the computer uses a predetermined program to determine that a problem has occurred. A control bar, Lube 2, is adapted to issue a command signal and corresponds to the power piston 21.
1 is immediately automatically connected to the neutral state or the open state, while the three-way switching valve 62 is automatically brought into the open state, and the port 53.5 of the spool valve 57 is automatically connected to the neutral state or the open state.
4, from the reservoir chamber 51 to the pressure regulating chamber 55 to the hydraulic circuit 6
Therefore, the power piston 21 is moved forward by the oil pressure in the lever chamber 24 and pressurizing chamber 23.

Therefore, in this case, the switching valve 62 remains switched, and the power piston 21 is pushed by controlling the amount by which the boat 53 of the spool valve 57 overlaps with the boat 52 by moving the main pump/socket Otsudo 3 forward and backward by operating the brake pedal 5. will be advanced.

When the driver performs predetermined braking in such a state of braking mode conversion, when the driver applies a pressing force to the brake pedal 5 that corresponds to the initial feeling of 1IIJ, the brake pedal 24 enters the reservoir chamber 24 via the open switching pulp 62 in the same manner as described above. Te spool pulp 57
Since the hydraulic pressure from the pressurizing chamber 23 is applied to the pressurizing chamber 51 of the control pulp 49 via the boat 37, the control valve 32 is applied to the pressurizing chamber 51 of the control pulp 49 via the boat 37. , and 45 are blocked,
Therefore, the pedal force applied to the brake pedal 5 is linearly applied in a balance between the set load and the resistance of the feeling spring 41 of the pedal force cylinder 10.
A pedal force similar to that of the above-mentioned double carbide O-rick servo braking operation is applied.

In this way, the power piston 21 is advanced to a predetermined value, the hydraulic pressure in the front hydraulic chamber 13 and the rear hydraulic chamber 16 is increased, and a predetermined braking force is transmitted to the front wheel brake 15 and the rear wheel brake 19, thereby causing the above-mentioned hydraulic Similar to the zero-risk servo braking mode, a deceleration corresponding to the pedal force is applied.

During this time, each vehicle speed sensor 6.6 detects the decelerated vehicle speed.
Even if ... detects the signal and sends the signal to the computer, as mentioned above, in this case, the control pulp 21 is not controlled by the computer due to an electrical system problem, and the driver cannot The booster braking is activated with the servo function in effect only by linear operation of the pedal force applied to the brake pedal 5 on the feeling spring 41.

Then, when the pressing force on the brake pedal 5 is reduced, the pushing force on the main bush 0 is canceled, but
At this time, the spool pulp 51 is retreated by the return spring 48 at its tip, and the boat 52 and the boat 53 of the spool valve 57 are displaced, and the hydraulic pressure to the pressurizing chamber 23 is reduced as in the above-mentioned embodiment, causing deceleration. will be resolved.

Also, if the pedal force is applied to the brake pedal 5,
The boats 53 and 52 of the spool pulp 57 are connected again, and the hydraulic pressure of the hydraulic pump 29 is applied to the pressurizing chamber 23 while the switching pulp 62 is always open, so that the power piston 21 moves forward again and a braking force is applied. become.

Therefore, the said! In case 9, the pedal force applied to the brake pedal 5 is the same as the pedal force cylinder 10, regardless of changes in the weight of the lliE, changes in the brake pad or shoe clearance, or even if there is a problem with the electrical system such as the computer 7. By simply applying the force to the feeling spring 41 in a linear response, large hydraulic braking can be obtained.Although it is only semi-automatic nervous braking, optimum deceleration can be obtained in response to the pedal force applied by the driver. It will be done.゛In addition, the computer stops the engine in any mode.
1, the #Jill pulp 27 is connected to the return connection, connected to the oil tank 30, the brake oil pressure becomes zero, and the parking brake is activated.

Therefore, the more automation and servo mechanisms are installed in the brake system, the more it is necessary to guarantee the braking mode conversion to manual braking using only pedal force as a minimum safety guarantee in the event that these complex mechanisms fail. However, in the present invention, if a hydraulic pressure loss unexpectedly occurs in the hydraulic circuit such as a failure of the hydraulic pump 29, the hydraulic pressure in the hydraulic pressure chamber 24 decreases, and therefore the pressure in the pressurizing chamber 23 decreases.
, and the oil pressure in the pressurizing chamber of the control pulp 32 decreases via the boat 31.2. When the depressing force applied to the brake pedal 5 presses the main bush rod 3, the hydraulic pressure of the pressurizing force v44 of the depressing force cylinder 10 is applied to the pressurizing chamber 2.
3. That is, the pressure in the front chamber of the control pulp 32 increases via the boat 45 and the boat (not shown) of the control pulp 32 as the pressure becomes higher than the pressure in the pressure chamber of the Funtrol pulp 32. The hydraulic pressure in the pressurizing chamber 44 causes the control pulp 32 to retreat against the return spring 34, and as a result, the pressurizing chamber 44
The hydraulic pressure is directed to the reservoir chamber 11 via the boat 45, 36, and therefore the hydraulic rigidity of the pressurized chamber 44 is lost.
As a result, the pressing force applied to the brake pedal 5 is simply a return spring of the pressurizing chamber 44 with respect to the main bush 03.

Only a small amount of deflection of the ring 43 is expended to push the sub-button rod 4 on its upper part through the pin 34 through a slight play in the rod receiver 26, so that the sub-button rod 4 is substantially The power piston 21 is immediately pushed forward, and the hydraulic pressure in the front hydraulic chamber 13 and rear hydraulic chamber 16 is pressurized to apply pressure to the front brake 15 and rear wheel brake 16.
The braking force is the same as that of a normal hydraulic brake system that uses simple pedal force without boosting.
, 1II of boosted hydraulic brake by 2°41
The first step is to get Ie automatically through the computer.
It has two systems: one system and a second hydraulic braking system that does not depend on the computer but uses boost power, and these two systems can be used to automatically control whether the electrical control is in a healthy operating state or when the electrical system is malfunctioning. It is designed so that it can be switched in a timely manner and in a mutually exclusive manner.

An automatically operated control valve and a normally open switching valve for the power piston are each independently and exclusively provided to ensure control of each booster hydraulic pressure and ensure smooth operation.

Furthermore, the fruit of this invention is Ili! Of course, the embodiments are not limited to the above-mentioned embodiments, and various embodiments can be adopted, such as providing different warning devices in the event of trouble in the electrical system or lack of hydraulic pressure. - <Effects of the Invention> As described above, according to the present invention, there is provided a brake system that has a hydraulic brake II that can provide extremely strong braking and can achieve boost braking. To obtain the optimum deceleration for the vehicle speed according to the applied pedal force, regardless of various conditions such as the load weight and changes in the brake pad shoe clearance of the brake mechanism depending on the applied pedal force. This is a system that enables automatic servo braking by controlling a control valve installed in the hydraulic circuit via hydraulic pressure based on detection signals of the applied pedal force and vehicle speed. By using two systems, one is a system that uses a boosting mechanism using a normally open cutting pulp when the pedal force is applied, and the other is a system that immediately responds to the pedal force that is applied in a non-servo manner. -The effective operation of the brake system always provides the optimum deceleration that immediately responds to the driver's sense of the actual speed applied, regardless of the different loading weight conditions or various changes in the brake mechanism, and moreover, without any shock. As a result, the driver's sense of safety, which is given top priority, is sufficiently guaranteed, and the automobile can reliably achieve a safe running state and driving state including deceleration and stopping, which is an excellent effect.

In addition, in contrast, there is a system that relies only on pedal force, which guarantees hydraulic braking operation using hydraulic auxiliary booster even if an electrical system failure occurs. By being made operable, the excellent effect of ensuring the above-mentioned safe driving optimum deceleration braking is produced.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a booster according to an embodiment of the present invention, Fig. 2 is an overall schematic system diagram of the embodiment, Fig. 3 is a perspective view of the sub-button rod and brake pedal together, and Fig. 4 is a reference vehicle speed. It is a corresponding graph diagram of the actual measured medium speed. 8... Master cylinder, 5... Brake pedal, 41... Depressing force detection mechanism, 31.57.59.60... Hydraulic circuit, 6... Vehicle speed sensor, 27... Control valve, 7 ...Computer, 21...Power piston, 62...Switching valve Applicant: Toyota Motor Corporation Procedural Amendment (Job) February 5, 1985 Manabu Shiga, Commissioner of the Patent Office 1, Display of the case Showa 1959 Patent Application No. 274276 2, Name of the invention Automotive brake system 3, Relationship to the case of the person making the amendment Patent applicant address 1 Toyota-cho, Soda City, Aichi Prefecture Name
(320) Toyota Motor Corporation Representative Matsumoto
Qing 4, Agent 〒105 5, Date of amendment order I will voluntarily correct it.

Claims (1)

[Claims] In a brake system in which a detection mechanism for detecting a pedal force applied to a brake pedal is connected to a master cylinder connected to a hydraulic circuit, and the pedal force detection mechanism and a vehicle speed sensor control a control valve of the hydraulic circuit via a computer. , a system in which braking force is transmitted to the power piston of the master cylinder by hydraulic pressure via control of a control valve provided in the hydraulic circuit, and hydraulic pressure controlled by the pedal effort from the brake pedal via a switching valve. A braking system for an automobile, characterized in that the two systems are automatically selected to be mutually exclusive based on the set deceleration by the computer. .