JPH0999831A - Hydraulic pressure boosting system for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure the boosting effect in the simultaneous operation of first and second hydraulic boosting devices, and to prevent the shock in operating a first operation member while a second operation member is operated. SOLUTION: The hydraulic pressure generated in a power steering device 7 for each steering operation is accumulated in an accumulator 30. When the steering operation is achieved during the braking operation, or the braking operation is achieved during the steering operation, an ECU 35 switches a feed valve 31 to the communication position II based on the brake operation signal from a brake switch 33 and the steering operation signal from a steering wheel switch 34, and the hydraulic pressure in the accumulator 30 is fed to the power steering device 7 to perform the power steering effect. When the steering operation is achieved even in the braking operation, the power steering effect is ensured, and no shocks in a steering wheel are generated even the braking operation is achieved in the steering operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic brake system which increases the braking force by boosting the pedaling force of a brake pedal in an automobile, for example, with the power of hydraulic fluid.
The present invention relates to a hydraulic pressure boosting system for a vehicle in which hydraulic fluid is shared with a power steering system that boosts steering force by boosting steering wheel operating force with hydraulic fluid power.

[0002]

2. Description of the Related Art Some vehicles such as automobiles use a hydraulic boosting system for a vehicle that boosts an operating force of an operating member by hydraulic pressure of hydraulic fluid and outputs the boosted force. This hydraulic boosting system for a vehicle is, for example, a hydraulic brake booster that operates by hydraulic pressure of hydraulic fluid in order to obtain a large braking force that cannot be obtained only by the pedaling force of the brake pedal or to reduce the pedaling force. Operated by a hydraulic brake system that uses a force device to boost the pedaling force to operate the master cylinder, or to obtain a large steering force that cannot be obtained only with the steering wheel operating force or to reduce the steering wheel operating force. There is a power steering system or the like in which a steering wheel is steered by boosting a steering wheel operating force by using a power steering device which is operated by a hydraulic pressure of liquid.

Among such hydraulic boosting systems for vehicles are, for example, a hydraulic boosting system for vehicles in which hydraulic fluid is shared between a hydraulic brake system and a power steering system.

FIG. 7 is a diagram showing an example of a conventional hydraulic boosting system for a vehicle, and FIG. 8 is a sectional view showing a hydraulic brake booster used in this system. In the figure, 1 is a vehicle hydraulic pressure boosting system (hereinafter also simply referred to as hydraulic pressure boosting system), 2 is a brake pedal, and 3 is operated by the brake pedal 2 to boost and output a pedal effort. An open center type hydraulic brake booster (hereinafter also simply referred to as a booster) 4 which is the hydraulic brake booster described above is a tandem type master cylinder 5 which is operated by the output of the booster 3 to generate a brake hydraulic pressure. A brake cylinder that operates with brake fluid pressure from the master cylinder 4 to generate a braking force for each wheel, 6 is a steering wheel, and 7 is an open center type that is operated by the steering wheel 6 and boosts and outputs the steering wheel operating force. The power steering device 8 is driven by the engine 9 to transfer the hydraulic fluid to the booster 3 and the power steering device. A pump for supplying 7 to the reservoir 10, a reservoir for storing the hydraulic fluid, and 11 for storing a hydraulic fluid for operating the booster 3 when the hydraulic fluid is not delivered from the pump 8 due to a failure of the pump 8 or the like. Is an accumulator for.

In the open center type booster 3, the gap between the control valves is maximized when the brake is not operated, and the hydraulic fluid flows freely, and the flow of the hydraulic fluid is restricted by narrowing the gap between the control valves during the operation. A hydraulic pressure is generated and output by the hydraulic pressure, and various structures are conventionally known. An example of the booster 3 is shown in FIG. Since the booster 3 is conventionally known, a portion related to a problem to be solved by the present invention will be briefly described here.

In the brake non-operating state shown in FIG. 8, the gap between the first annular groove 12 and the second annular groove 13 is the maximum, and the second annular groove 13 and the third annular groove 14 are the same.
And the third annular groove 14 and the fourth annular groove 15 communicate with each other. Therefore, the pump 8
The hydraulic fluid discharged from the booster 3 of the open center type has a passage 16, a second annular groove 13, a first annular groove 12 and a second annular groove 12.
Gap between the annular groove 13, the first annular groove 12 and the passage 1
It flows to the open center type power steering device 7 through 7, and further circulates to the reservoir 10 again through the maximum gap of the control valve (not shown) of the power steering device 7. In that case, the gap between the first annular groove 12 and the second annular groove 13 and the clearance of the control valve of the power steering device 7 are both maximum,
Almost no hydraulic pressure is generated in the circulating hydraulic fluid.

When a brake operation is performed by depressing the brake pedal 2 in this state, the input rod 18 advances, so that the lever 19 rotates and the spool 20 advances.
Therefore, the gap between the first annular groove 12 and the second annular groove 13 is narrowed, and the second annular groove 13 and the third annular groove 1 are formed.
4 communicates with each other, and the third annular groove 14 and the fourth annular groove 15 are disconnected from each other. When the gap between the first and second annular grooves 12 and 13 is reduced, a hydraulic pressure is generated in the second annular groove 13. This hydraulic pressure is applied to the second annular groove 13 and the third annular groove 14
Between them, the radial passage 21, the longitudinal passage 22
And is introduced into the power chamber 24 through the radial passage 23 and acts on the power piston 25.
Generates a broom operation force that boosts the pedal effort, and this brake operation force is output from the output rod 26 to operate the master cylinder 4 and the brake is operated.

When the brake operation is released by releasing the brake pedal 2, the input rod 18 and the spool 2 are released.
0 retracts to the non-actuated position shown in FIG.
And the fourth annular groove 15 communicate with each other, the second annular groove 13 and the third annular groove 14 are blocked from each other, and the gap between the first annular groove 12 and the second annular groove 13 is maximized. For this reason,
The hydraulic fluid in the power chamber 24 passes through the passages 23, 22, 21, the third annular groove 14, the gap between the third annular groove 14 and the fourth annular groove 15, the fourth annular groove 15 and the passage 27, and then becomes a reservoir. 1
It is discharged to 0. As a result, the power piston 25 retracts to the non-actuated position, the brake operating force disappears, the master cylinder 4 returns to the non-actuated state, and the brake actuation is released. Further, since the gap between the first and second annular grooves 12 and 13 is maximized, the hydraulic pressure generated in the second annular groove 13 disappears.

The hydraulic boosting system 1 configured as described above
8 is in the state shown in FIG. 8 when both the hydraulic brake and the power steering are inoperative. Therefore, the hydraulic fluid is circulated through the reservoir 10, the open center type hydraulic brake booster 3, the open center type power steering device 7, and the reservoir 10 by the pump 8 as described above. At this time, the flow of the circulating hydraulic fluid is not restricted, and almost no hydraulic pressure is generated in the hydraulic fluid.

On the other hand, the open center type power steering device 7 is a conventional general open center type power steering device, and when it is not operated, the clearance of the control valve (not shown) provided inside is the maximum. Therefore, the hydraulic fluid discharged from the pump 8 and flowing into the power steering device 7 through the booster 3 is returned to the reservoir 10 through the gap of the control valve without being throttled. Therefore,
When the power steering device 7 is not operated, no hydraulic pressure is generated in the hydraulic fluid upstream of the control valve.

When the steering operation is performed by operating the steering wheel 6, the clearance of the control valve is narrowed, so that hydraulic pressure is generated on the upstream side of the control valve. Since this hydraulic pressure acts on the power piston (not shown) of the power steering device 7, the power piston operates to output a steering force that is a boost of the steering wheel operating force, and the wheels are steered by this steering force. Thus, the power steering operation is performed.

[0012]

By the way, in such a hydraulic boosting system 1, the gap between the first annular groove 12 and the second annular groove 13 of the booster 3 is narrowed during the brake operation. A part of the hydraulic fluid discharged from the pump 8 is introduced into the power chamber 24 of the booster 3 and consumed as the power piston 25 strokes. Therefore, the hydraulic fluid temporarily supplied to the power steering device 7 decreases. If the steering operation is performed at this time, the boosting action of the power steering device 7 may not be sufficiently performed.

When the brake operation is performed while the vehicle is turning by the steering operation, a part of the hydraulic fluid discharged from the pump 8 is consumed by the stroke of the power piston 25 of the booster 3, so that the power steering apparatus is operated. The amount of hydraulic fluid supplied to 7 is temporarily reduced. Therefore, the boosting action of the power steering device 7 is not sufficiently performed, which may cause a steering wheel shock.

The present invention has been made in view of such circumstances, and an object thereof is to provide first and second hydraulic boosters even when the first and second hydraulic boosters are simultaneously operated. Is capable of reliably performing each boosting action, and does not cause a shock to the second operating member even if the first operating member is operated while the second operating member is being operated. It is to provide a boost system.

[0015]

In order to solve the above-mentioned problems, the invention of claim 1 provides a reservoir for storing a working fluid,
A pump that sucks and discharges the working fluid in the reservoir, a first operating member, and the working fluid that is normally discharged from the pump freely flows through a gap between the first control valve provided therein, The hydraulic fluid generates a first hydraulic pressure by narrowing the gap of the first control valve when the first operating member is operated, and acts on the first power piston provided inside. Thus, an open center type first hydraulic pressure booster that boosts and outputs the operating force of the first operating member by the first hydraulic pressure, a second operating member, and the first hydraulic pressure multiplying device during normal operation. The hydraulic fluid discharged from the pump flowing through the force device is provided inside the second
Flowing freely through the gap of the control valve to recirculate to the reservoir,
When the second operation member is operated, the hydraulic fluid generates a second hydraulic pressure by narrowing the gap of the second control valve, and the second hydraulic pressure acts on the second power piston provided inside. An open center type second hydraulic pressure booster that boosts and outputs the operating force of the second operating member by the second hydraulic pressure, and at least one of the first hydraulic pressure and the second hydraulic pressure. An accumulator for storing the hydraulic pressure of the second hydraulic pump, a supply valve for supplying or stopping the hydraulic pressure stored in the accumulator to the second hydraulic booster, and the first operating member and the second operating member both operate. A control device that controls the supply valve so that the hydraulic pressure of the accumulator is supplied to the second hydraulic booster only when the first operating member and the second operating member are both Operated It is characterized by supplying the fluid pressure of the accumulator in the second fluid pressure booster to come.

Further, the invention of claim 2 is provided in parallel with at least a part of the first passage of the hydraulic fluid which connects between the first hydraulic booster and the second hydraulic booster. A parallel passage that connects between the first hydraulic booster and the second hydraulic booster is provided, and the accumulator and the supply valve are arranged in the parallel passage. It has a feature.

According to a third aspect of the present invention, the second passage for the hydraulic fluid connecting the pump and the first hydraulic pressure booster and the second hydraulic pressure booster are connected to the first hydraulic pressure. It is characterized in that it has a bypass passage for connecting the booster device by bypass, and that the accumulator and the supply valve are provided side by side in this bypass passage.

Further, in the invention of claim 4, from the connection point of the bypass passage of the second passage to the first hydraulic booster side,
It is characterized in that there is provided a flow rate limiting valve in which an unlimited position that does not limit the flow rate of the hydraulic fluid in a normal state and a limit position that limits the flow rate of the hydraulic fluid when operated by the control device are set. .

Further, a fifth aspect of the present invention includes a reservoir for storing the working fluid, a pump for sucking and discharging the working fluid in the reservoir, a first operating member, and the working fluid normally discharged from the pump. Freely flows in the gap of the first control valve provided therein, and when the first operation member is operated, the gap of the first control valve is narrowed so that the hydraulic fluid becomes the first fluid.
By generating a hydraulic pressure and acting this first hydraulic pressure on a first power piston provided inside, the first hydraulic piston
Through an open-center type first hydraulic booster that boosts and outputs the operating force of the operating member by the first hydraulic pressure, a second operating member, and normally the first hydraulic booster. The flowing working fluid discharged from the pump freely flows through the gap of the second control valve provided inside and recirculates to the reservoir, and the second control is performed when the second operation member is operated. By narrowing the gap of the valve, the hydraulic fluid generates a second hydraulic pressure, and the second hydraulic pressure acts on the second power piston provided inside, so that the operating force of the second operating member is increased. An open-center type second hydraulic booster that boosts and outputs the second hydraulic pressure, an accumulator that stores at least one of the first hydraulic pressure and the second hydraulic pressure, and an accumulator The hydraulic pressure that has been applied to the first hydraulic booster A supply valve for supplying or stopping supply, a first passage for the hydraulic fluid connecting the pump and the first hydraulic pressure booster, the first passage and the second hydraulic pressure booster, A bypass passage for bypassing and connecting the first hydraulic booster, a normally open first opening / closing valve provided in a first passage downstream of a branch point of the bypass passage, and a bypass passage The normally closed second on-off valve and the hydraulic pressure of the accumulator are supplied to the first hydraulic booster only when both the first operating member and the second operating member are operated, and the pump is supplied from the pump. The first operation includes the supply valve and a controller that controls the first and second opening / closing valves so as to supply the discharged hydraulic fluid to the second hydraulic booster through the bypass passage. The member and the second operating member When the hydraulic pressure of the accumulator is supplied to the first hydraulic booster, the hydraulic fluid discharged from the pump is supplied to the second hydraulic booster. There is.

Further, the invention of claim 6 is provided in parallel with at least a part of the first passage on the downstream side of the first opening / closing valve, and connects the pump and the first hydraulic booster. Is provided with the parallel passage, and the accumulator and the supply valve are arranged in the parallel passage.

Further, the invention of claim 7 limits the flow rate of the working fluid when it is operated by the control device and an unlimited position where the flow rate of the working fluid is not limited in at least part of the first passage. It is characterized in that a flow rate limiting valve whose limit position is set is provided.

Further, in the invention of claim 8, the first operating member is a brake operating member, the first hydraulic booster is a hydraulic brake booster, and the second operating member is a steering handle. The second hydraulic booster is a power steering device.

[0023]

According to the present invention thus configured, the first
And for each operation of at least one of the second operation member, the first operation
At least one of the first hydraulic pressure and the second hydraulic pressure is generated in at least one of the second hydraulic booster, and this hydraulic pressure is stored in the accumulator. Then, only when both the first and second operating members are operated, the operation of the supply valve is controlled by the control device, and the hydraulic pressure stored in this accumulator is either the first or the second hydraulic booster. It is supplied to one side, and a boosting action is performed by one of the first and second hydraulic boosters. Thus, even if the amount of hydraulic fluid supplied from the pump to either one of the first and second hydraulic boosters temporarily decreases, it is replenished by the hydraulic pressure stored in the accumulator, or The working fluid discharged from the pump is supplied to either one of the second hydraulic booster and the hydraulic pressure stored in the accumulator is supplied to the other. Therefore, even if one of the first and second operating members operates the other during operation, the first
It is possible to prevent a temporary decrease in the amount of hydraulic fluid supplied to either one of the hydraulic pressure booster and the second hydraulic pressure booster, so that the boosting action of both the first hydraulic pressure booster and the second hydraulic pressure booster is reliably performed. Even if the first operating member is operated during the operation of the second operating member, the shock does not occur in the second operating member.

In particular, in the inventions of claims 4 and 7, the control device controls the flow rate restricting valve, whereby the first
And other than the operation of at least one of the second operation members,
When the hydraulic pressure stored in the accumulator is equal to or lower than the predetermined pressure, the hydraulic pressure is stored in the accumulator.

According to the eighth aspect of the invention, the hydraulic pressure generated by at least one of the booster and the power steering device is accumulated in the accumulator for each operation of at least one of the brake operation and the steering operation. When the steering operation is performed during the braking operation, or when the braking operation is performed during the steering operation, the control device operates and controls the supply valve, so that the hydraulic pressure of the accumulator is applied to either the power steering device or the booster. It is supplied and booster boosting and power steering operations are performed. In this way, if the steering operation is performed even during the braking operation, the power steering operation is surely performed, and the steering wheel shock is not generated even if the braking operation is performed during the steering operation.

[0026]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a first embodiment of a vehicle hydraulic boosting system according to the present invention. The same components as those of the conventional system shown in FIGS. 7 and 8 are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 1, in the hydraulic boosting system 1 of the first embodiment, a power steering passage (hereinafter, also referred to as PS passage) 28 connecting a passage 17 of a booster 3 and a power steering device 7 is provided. Parallel passage 29 provided in parallel with a portion 28a of the vehicle, an accumulator 30 provided in the parallel passage 29 for accumulating hydraulic pressure generated when the power steering device 7 is operated, and a downstream side of the accumulator 30. And a normally closed supply valve 31 which is composed of a solenoid valve and has two positions, a shutoff position I and a communication position II, and is provided on the upstream side of the accumulator 30.
A check valve 32 that allows only the flow of hydraulic fluid from the upstream side to the downstream side, and an electronic control that controls the operation of the supply valve 31 based on a brake operation signal from the brake switch 33 and a steering operation signal from the handlebar switch 34. A device (hereinafter, also referred to as an ECU) 35.

The brake switch 33 is a switch that operates when a brake operation is performed by stepping on the brake pedal 2, and a pedal force sensor provided on the brake pedal 2, a stroke sensor for detecting a pedal stroke, and a master cylinder 4 are generated. It is composed of a hydraulic pressure pickup or a brake lamp switch for detecting the brake hydraulic pressure.

The steering wheel switch 34 is a switch that operates when the steering operation is performed by operating the steering wheel 6, and is composed of a steering angle detection sensor or the like for detecting the steering angle of the steering wheel. The other structure of the first embodiment is the same as the structure of the conventional system shown in FIGS. 7 and 8.

The operation of the first embodiment thus constructed will be described. Since the brake operation by the booster 3 and the power steering operation by the power steering device 7 in the first embodiment are the same as those in the above-mentioned conventional example, the description thereof will be omitted.

In the first embodiment, the hydraulic pressure generated on the upstream side of the control valve of the power steering device 7 every time the steering operation is performed by the operation of the handle 6 is accumulated in the accumulator 30 through the check valve 32. . When a brake operation is performed in a state where a predetermined pressure is accumulated in the accumulator 30, the brake switch 33 is turned on, a brake operation signal is supplied to the ECU 35, and the power steering device 7 is operated as described above.
The amount of hydraulic fluid supplied from the pump 8 to the pump is temporarily reduced. When the steering operation is performed by operating the steering wheel 6 during the braking operation, the steering wheel switch 34 is turned on, the steering operation signal is supplied to the ECU 35, and the clearance of the control valve of the power steering device 7 is narrowed.

The ECU 35 switches the supply valve 31 to the communication position II based on both operation signals. As a result, the hydraulic pressure accumulated in the accumulator 30 is supplied to the upstream side of the control valve in the power steering device 7 where the clearance is narrowed and acts on the power piston, and the power steering device 7 doubles the operating force of the steering wheel. The power steering operation is performed by the applied steering force. Thus, in the first embodiment, the accumulator 3 is operated even if the handle 6 is operated while the amount of hydraulic fluid from the pump 8 supplied to the power steering device 7 is temporarily reduced by the brake operation.
Since the hydraulic pressure accumulated at 0 is supplied, the boosting action of the power steering device 7 can be reliably performed.

When the brake operation is performed during the power steering operation by operating the steering wheel 6, the brake operation is performed and the amount of the hydraulic fluid from the pump 8 supplied to the power steering device 7 is temporarily changed as described above. Decrease. Since both operation signals from the brake switch 33 and the handlebar switch 34 are input, the ECU 35 connects the supply valve 31 to the communication position II as described above.
Switch to. As a result, the hydraulic pressure of the accumulator 30 is supplied to the power steering device 7. Therefore, even if the amount of hydraulic fluid supplied from the pump 8 to the power steering device 7 is temporarily reduced, the power steering device 7
The boosting action of does not change. In this way, even if the brake operation is performed during the steering operation, the boosting action of the power steering device 7 does not change, so that the steering wheel shock does not occur.

FIG. 2 is a diagram showing a second embodiment of the present invention. The same components as those in the first embodiment shown in FIG. 1 and the conventional system shown in FIGS. 7 and 8 are designated by the same reference numerals, and detailed description thereof will be omitted.

This second embodiment is provided in a part 28a of the PS passage 28 in the first embodiment described above and is composed of an electromagnetic valve, and has two positions, a flow rate unlimited position I and a flow rate limited position II by an orifice 36a. A set flow rate limiting valve 36 and a pressure switch 37 that detects the hydraulic pressure of the accumulator 30 are provided.

The flow rate limiting valve 36 is connected to the ECU 35 and is controlled by the ECU 35. The flow rate limiting valve 36 is normally in the flow rate unlimited position.
It is set to I so as not to limit the flow rate of the hydraulic fluid flowing through the part 28a of the PS passage 28 at all, but when it is set to the flow rate limiting position II, a part 2 of the PS passage 28 is formed.
The flow rate of the hydraulic fluid flowing through 8a is restricted so that hydraulic pressure is generated on the upstream side. Further, the pressure switch 37 is connected to the ECU 35 and supplies the detected hydraulic pressure of the accumulator 30 to the ECU 35.
The other structure of the second embodiment is the same as the structure of the first embodiment shown in FIG. 1 and the structure of the conventional system shown in FIGS. 7 and 8.

The operation of the second embodiment thus constructed will be described. Since the brake operation by the booster 3 and the power steering operation by the power steering device 7 in the second embodiment are the same as those in the above-mentioned conventional example, the description thereof will be omitted. In addition, the operation of the accumulator 30 and the supply valve 31 in the second embodiment is also the same as in the first embodiment described above.
Since this is the same as the embodiment, its description is omitted. Further, in the second embodiment, when the hydraulic pressure of the accumulator 30 is below a predetermined value, the pressure switch 37 is turned on and the ECU 3
A hydraulic pressure decrease signal is output to 5. The ECU 35 switches the flow rate limiting valve 36 to the flow rate limiting position II based on this hydraulic pressure decrease signal. Therefore, the amount of the hydraulic fluid flowing through the part 28a of the PS passage 28 is limited, so that hydraulic pressure is generated on the upstream side of the flow rate limiting valve 36, and this hydraulic pressure is accumulated in the accumulator 30. In order to ensure the power steering operation, the flow rate limiting valve 36 is set to the unlimited position I during steering operation.

As described above, in the second embodiment, not only the hydraulic pressure generated by each steering operation in the first embodiment is accumulated in the accumulator 30, but also the hydraulic pressure generated by the switching operation of the flow rate limiting valve 36. Is also accumulated in the accumulator 30. As a result, the pressure accumulated in the accumulator 30 can be performed in addition to the steering operation, and the pressure accumulated in the accumulator 30 can be further ensured. In particular, since the ECU 35 switches the flow rate limiting valve 36 when both the brake and the steering are not operated and the hydraulic pressure of the accumulator 30 is equal to or lower than a predetermined value, the brake operation and the steering operation are not affected. , It becomes possible to store the pressure in the accumulator 30.

FIG. 3 is a diagram showing a third embodiment of the present invention. The same components as those in the first embodiment shown in FIG. 1 and the conventional system shown in FIGS. 7 and 8 are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 3, the hydraulic boosting system 1 according to the third embodiment has a pump 1 and a passage 1 of a booster 3.
A bypass passage 39 that directly connects the supply passage 38 and the PS passage 28 that connect between the six and bypasses the booster 3 is provided. Furthermore, the hydraulic boosting system 1 of the third embodiment
Is provided in the bypass passage 39, includes the accumulator 30, the supply valve 31, and the check valve 32 in the first embodiment, and also has the brake switch 33.
An ECU 35 that controls the supply valve 31 based on each operation signal from the handlebar switch 34 is provided.

In the third embodiment, the hydraulic pressure generated by the booster 3 for each brake operation and the hydraulic pressure generated by the power steering device 7 for each steering operation are accumulated in the accumulator 30. . Another configuration of this third embodiment is similar to that shown in FIGS.
The configuration is the same as that of the conventional system shown in FIG.

The operation of the third embodiment thus constructed will be described. In the third embodiment, similar to the first embodiment, the hydraulic pressure generated by the power steering device 7 for each steering operation is not only accumulated in the accumulator 3 but also generated by the booster 3 for each braking operation. The hydraulic pressure is also accumulated in the accumulator 30. The other operation of the third embodiment is the same as that of the first embodiment described above, and the description thereof will be omitted.

Therefore, also in the third embodiment, if the steering wheel 6 is operated even during the braking operation, the power steering operation is performed reliably, and even if the braking operation is performed during the steering operation, the power steering is performed. Since the boosting action of the device 7 is surely performed, a handle shock does not occur.

FIG. 4 is a diagram showing a fourth embodiment of the present invention. The same components as those in the above-described embodiments and the conventional system are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 4, the hydraulic boosting system 1 of the fourth embodiment has a flow restricting valve 36 similar to that of the second embodiment shown in FIG. 2 in the third embodiment shown in FIG. A pressure switch 37 for detecting the hydraulic pressure of the accumulator 30 is provided. The flow rate limiting valve 36 is provided in the supply passage 38 on the downstream side of the branch point with the bypass passage 39. Then, similarly to the second embodiment, the ECU 35 controls the pressure switch 3
When the hydraulic pressure of the accumulator 30 is equal to or lower than a predetermined value based on the hydraulic pressure signal from 7, the flow rate limiting valve 36 is set to the flow rate limiting position II.
Switch to. Therefore, the amount of the hydraulic fluid flowing through the supply passage 38 is limited, and the hydraulic pressure generated on the upstream side of the flow rate limiting valve 36 is accumulated in the accumulator 30.

In order to ensure that the hydraulic brake operation or the power steering operation is performed, the flow rate limiting valve 36 is operated during the brake operation or the steering operation.
Is set to unlimited position I.

Thus, in the fourth embodiment, not only the hydraulic pressure generated by each brake operation and each steering operation is accumulated in the accumulator 30, but also the hydraulic pressure generated by the switching operation of the flow rate limiting valve 36. Is stored in. As a result, the accumulator 30
Accumulation of pressure becomes even more reliable. In particular, when both the brake and the steering are not operated and the hydraulic pressure of the accumulator 30 is equal to or lower than a predetermined value, the ECU 35 causes the flow control valve 3 to operate.
Since 6 is switched, pressure can be accumulated in the accumulator 30 without affecting brake operation or steering operation. Other configurations and other operational effects of the fourth embodiment are the same as the configurations and operational effects of the third embodiment described above.

FIG. 5 is a diagram showing a fifth embodiment of the present invention. The same components as those in the above-described embodiments and the conventional system are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 5, the hydraulic boosting system 1 according to the fifth embodiment is provided with a parallel passage 40 provided in parallel with a portion 38a of the supply passage 38 and the parallel passage 40. An accumulator 30 that accumulates the hydraulic pressure generated when the booster 3 is operated, and a normally-closed supply that is provided on the downstream side of the accumulator 30 and includes an electromagnetic valve and that has two positions, a shutoff position I and a communication position II. A valve 31, a check valve 32 provided on the upstream side of the accumulator 30 and allowing only the flow of the working fluid from the upstream side to the downstream side, and a supply passage 38 on the upstream side of the branch point of the parallel passage 40. Together with a solenoid valve, communication position I
And a shut-off position II, the normally open first opening / closing valve 41 and the supply passage 38 upstream of the first opening / closing valve 41.
And the PS passage 28 are provided in a bypass passage 39 that directly connects the booster 3 by bypassing the booster 3 and is composed of a solenoid valve, and is a normally closed second on-off valve in which two positions, a shutoff position I and a communication position II, are set. 42, and an ECU 35 that controls each switching operation of the supply valve 31, the first and second opening / closing valves 41, 42 based on each operation signal from the brake switch 33 and the handle switch 34. The other configuration of the fifth embodiment is the same as the configuration of the conventional system shown in FIGS. 7 and 8 described above.

The operation of the fifth embodiment thus constructed will be described. Since the brake operation by the booster 3 and the power steering operation by the power steering device 7 in the fifth embodiment are the same as those in the above-mentioned conventional example, the description thereof will be omitted.

In the fifth embodiment, similarly to the third and fourth embodiments, the hydraulic pressure generated by each brake operation and the hydraulic pressure generated by each steering operation are accumulated in the accumulator 30 through the check valve 32. . When a brake operation is performed in a state where a predetermined pressure is accumulated in the accumulator 30, the brake switch 33 is turned on as described above, a brake operation signal is supplied to the ECU 35, and a pump supplied to the power steering device 7. The amount of hydraulic fluid from 8 is generally reduced. When the steering operation is performed during the brake operation, the steering wheel switch 34 is turned on and the steering operation signal is changed to EC.
While being supplied to U35, the clearance of the control valve of the power steering device 7 is narrowed.

Based on both operation signals, the ECU 35 switches the supply valve 31 to the communication position II, switches the first opening / closing valve 41 to the shutoff position II, and further switches the second opening / closing valve 42 to the communication position II. As a result, the hydraulic pressure accumulated in the accumulator 30 causes the supply valve 31, the supply passage 38, the passage 16 of the booster 3, the second annular groove 13, the third annular groove 14, the passage 21,
It is supplied to the power chamber 24 through 22 and 23, and the hydraulic pressure of the accumulator 30 causes the booster 3 to operate and output. On the other hand, the hydraulic fluid discharged from the pump 8 is not supplied to the booster 3 because the first opening / closing valve 41 is set to the shutoff position II, and the bypass passage 39, the second opening / closing valve 42 and the PS passage are provided. The power steering device 7 is directly supplied to the power steering device 7 through 28, and the power steering operation is performed by the hydraulic pressure generated by limiting the hydraulic fluid from the pump 8.

As described above, in the simultaneous operation of the brake and the steering, the brake boosting action of the booster 3 is surely performed by the hydraulic pressure of the accumulator 30, and the steering boosting of the power steering device 7 is performed by the hydraulic fluid from the pump. The action is surely performed. In that case, since the amount of hydraulic fluid supplied to the power steering device 7 does not decrease, steering wheel shock does not occur. Other operational effects of the fifth embodiment are the same as those of the first embodiment.

The supply passage 3 near the discharge port of the pump 8
8 is further provided with a pressure switch which is turned on when the hydraulic pressure on the discharge side of the pump 8 exceeds a predetermined value, and an ON signal of this pressure switch is input to the ECU 35. When the brake operation is performed when the pump 8 is out of order, the ECU 35 determines that the pump 8 is out of order if the ON signal of the pressure switch is not input even though the brake operation signal is input. , The first and second supply valves 31 and 41 are switched to the communicating position II and the shut-off position II, respectively. As a result, even if the pump 8 fails, the brake operation can be reliably performed by the hydraulic pressure of the accumulator 30. Therefore, the safety is improved, and the accumulator valve 43 provided in the emergency accumulator 11 and the booster 3 as shown in FIG. 7 for controlling the supply and discharge of the hydraulic pressure of the accumulator 30 can be omitted.

FIG. 6 is a diagram showing a sixth embodiment of the present invention. The same components as those in the above-described embodiments and the conventional system are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 6, in the hydraulic boosting system 1 of the sixth embodiment, a flow rate restriction similar to that of the second and fourth embodiments is provided in a part 38a of the supply passage 38 in the fifth embodiment. A valve 36 is provided. Further, in place of the normally closed second on-off valve 42 of the fifth embodiment, a position I for connecting the pump 8 to the booster 3 and a position II for connecting the pump 8 to the bypass passage 39 are provided. A flow path switching valve 44 is provided. The flow passage switching valve 44 is normally set to the position I and is controlled to be switched by the ECU 35. In that case, the position I of the flow path switching valve 44
The switching control between the position and the position II is performed by the second opening / closing valve 42 of the fifth embodiment.
Is the same as the control of. Needless to say, the second opening / closing valve 42 may be used as in the fifth embodiment.

The flow rate limiting valve 36 not only accumulates the hydraulic pressure generated in each brake operation and each steering operation in the accumulator 30 as in the second and fourth embodiments, but also switches the flow rate limiting valve 36. The hydraulic pressure generated by is also accumulated in the accumulator 30. As a result, the accumulated pressure in the accumulator 30 becomes even more reliable.
In particular, when both the brake and the steering are not operated and the hydraulic pressure of the accumulator 30 is below a predetermined value,
Since the ECU 35 switches the flow rate limiting valve 36, the accumulator 30 can accumulate pressure without affecting brake operation and steering operation. Other configurations and other operational effects of the sixth embodiment are the same as the configurations and operational effects of the fifth embodiment described above.

The present invention is not limited to the hydraulic brake system and the power steering system, and is provided with two open center type hydraulic boosters which share the working fluid, and other hydraulic boost systems for vehicles. Can also be applied to.

[0059]

As is apparent from the above description, according to the hydraulic boosting system for a vehicle of the present invention, when the second operating member is operated even while the first operating member is being operated, 1
And each boosting action by the second hydraulic booster can be surely performed. Further, it is possible to prevent a shock from being generated in the second operating member when the first operating member is operated while the second operating member is being operated.

Particularly, according to the inventions of claims 4 and 7,
When the hydraulic pressure stored in the accumulator is equal to or lower than the predetermined pressure, the hydraulic pressure can be reliably stored in the accumulator even when the operation of at least one of the first and second operating members is not performed. As a result, the boosting action of the second hydraulic booster can be performed more reliably.

Further, according to the invention of claim 8, when the steering operation is performed even during the braking operation, both the booster boosting operation and the power steering operation can be surely performed, and the braking operation is performed during the steering operation. If you do, you can prevent handle shock.

Further, the emergency accumulator used in the conventional brake system using the open center type hydraulic brake booster and the accumulator valve for controlling the supply / discharge of the hydraulic pressure to / from the emergency accumulator can be dispensed with. .

[Brief description of drawings]

FIG. 1 is a first hydraulic boosting system for a vehicle according to the present invention.
It is a figure showing an example.

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 showing a fourth embodiment of the present invention.

FIG. 5 is a diagram showing a fifth embodiment of the present invention.

FIG. 6 is a diagram showing a sixth embodiment of the present invention.

FIG. 7 is a diagram showing an example of a conventional vehicle hydraulic boosting system.

FIG. 8 is a diagram showing an example of an open center type hydraulic brake booster.

[Explanation of symbols]

1 ... Hydraulic boosting system for vehicle, 2 ... Brake pedal, 3
… Open center type hydraulic brake booster,
4 ... Master cylinder, 5 ... Brake cylinder, 6 ... Handle, 7 ... Open center type power steering device, 8 ... Pump, 10 ... Reservoir, 12 ... First annular groove,
13 ... 2nd annular groove, 14 ... 2nd annular groove, 15 ... 4th annular groove, 18 ... Input rod, 19 ... Lever, 20 ... Spool, 24 ... Power chamber, 25 ... Power piston, 26 ... Output rod, 28 … Power steering passage, 29,40…
Parallel passage, 30 ... Accumulator, 31 ... Supply valve, 32
… Check valves, 33… Brake switches, 34…
Handle switch, 35 ... Electronic control unit (ECU), 3
6 ... Flow rate limiting valve, 37 ... Pressure switch, 38 ... Supply passage, 39 ... Bypass passage, 41 ... First opening / closing valve, 42 ... Second opening / closing valve, 44 ... Flow path switching valve

Claims (8)

[Claims] 1. A reservoir for storing hydraulic fluid, a pump for sucking and discharging the hydraulic fluid in the reservoir, and
The operating fluid and the hydraulic fluid normally discharged from the pump normally flow freely in the gap between the first control valves provided inside, and narrow the gap between the first control valves when operating the first operating member. As a result, the hydraulic fluid generates a first hydraulic pressure and acts on the first power piston provided inside, so that the operating force of the first operating member is changed by the first hydraulic pressure. The open center type first hydraulic booster for boosting and outputting, the second operating member, and the operation discharged from the pump, which normally flows through the first hydraulic booster. The liquid freely flows through the gap of the second control valve provided inside and recirculates to the reservoir,
By narrowing the gap of the second control valve when operating the operating member, the hydraulic fluid generates a second hydraulic pressure and
A second hydraulic booster of an open center type, which hydraulically acts on a second power piston provided inside to boost the operating force of the second operating member by the second hydraulic pressure and output the boosted force. An accumulator that stores at least one of the first hydraulic pressure and the second hydraulic pressure, and a supply valve that supplies or stops the hydraulic pressure stored in the accumulator to the second hydraulic booster. And a control device that controls the supply valve so that the hydraulic pressure of the accumulator is supplied to the second hydraulic booster only when both the first operating member and the second operating member are operated. And a hydraulic pressure booster for a vehicle, wherein the hydraulic pressure of the accumulator is supplied to the second hydraulic pressure booster when both the first operating member and the second operating member are operated. system. 2. The first hydraulic pressure is provided in parallel with at least a part of a first passage of the hydraulic fluid that connects the first hydraulic booster and the second hydraulic booster. The parallel passage which connects between the booster and the second hydraulic booster is provided, and the accumulator and the supply valve are arranged in the parallel passage. The vehicle hydraulic boosting system described. 3. The second hydraulic pressure booster and the second passage for the hydraulic fluid connecting between the pump and the first hydraulic pressure booster bypass the first hydraulic pressure booster. The hydraulic boosting system for a vehicle according to claim 1, further comprising a bypass passage connected to the vehicle, wherein the accumulator and the supply valve are provided in the bypass passage. 4. An unlimited position where the flow rate of the hydraulic fluid is not normally limited from the connection point of the bypass passage of the second passage to the first hydraulic booster side, and the actuation when actuated by the control device. 4. The hydraulic boosting system for a vehicle according to claim 3, further comprising a flow rate limiting valve having a limit position for limiting the flow rate of the liquid. 5. A reservoir for storing hydraulic fluid, a pump for sucking and discharging the hydraulic fluid in the reservoir, and a first
The operating fluid and the hydraulic fluid normally discharged from the pump normally flow freely in the gap between the first control valves provided inside, and narrow the gap between the first control valves when operating the first operating member. As a result, the hydraulic fluid generates a first hydraulic pressure and acts on the first power piston provided inside, so that the operating force of the first operating member is changed by the first hydraulic pressure. The open center type first hydraulic booster for boosting and outputting, the second operating member, and the operation discharged from the pump, which normally flows through the first hydraulic booster. The liquid freely flows through the gap of the second control valve provided inside and recirculates to the reservoir,
By narrowing the gap of the second control valve when operating the operating member, the hydraulic fluid generates a second hydraulic pressure and
A second hydraulic booster of an open center type, which hydraulically acts on a second power piston provided inside to boost the operating force of the second operating member by the second hydraulic pressure and output the boosted force. An accumulator that stores at least one of the first hydraulic pressure and the second hydraulic pressure; and a supply valve that supplies or stops the hydraulic pressure stored in the accumulator to the first hydraulic booster. A first passage for the hydraulic fluid that connects between the pump and the first hydraulic booster; the first passage and the second hydraulic booster; and the first hydraulic booster. A bypass passage for connecting the bypass passage, a normally open first opening / closing valve provided in a first passage downstream from a branch point of the bypass passage, and a normally closed second opening / closing valve provided in the bypass passage. Valve, the first operating member and the second operating member The hydraulic pressure of the accumulator is supplied to the first hydraulic booster only when both are operated, and the hydraulic fluid discharged from the pump is supplied to the second hydraulic booster through the bypass passage. As described above, the supply valve and the control device that controls the first and second opening / closing valves are provided, and the hydraulic pressure of the accumulator is set to the above when the first operating member and the second operating member are both operated. A hydraulic boosting system for a vehicle, wherein the hydraulic fluid discharged from the pump is supplied to the second hydraulic booster while being supplied to a first hydraulic booster. 6. A parallel passage that is provided in parallel with at least a part of the first passage downstream of the first opening / closing valve and connects the pump and the first hydraulic booster to each other. The hydraulic boosting system for a vehicle according to claim 5, wherein the accumulator and the supply valve are arranged in the parallel passage. 7. An unrestricted position that does not normally limit the flow rate of the working fluid and a limit position that limits the flow rate of the working fluid when operated by the control device are set in at least a part of the first passage. A hydraulic boosting system for a vehicle according to claim 2 or 6, further comprising a flow rate limiting valve. 8. The first operating member is a brake operating member, the first hydraulic booster is a hydraulic brake booster, the second operating member is a steering handle, and the second hydraulic pressure multiplier is provided. 8. The hydraulic boosting system for a vehicle according to claim 1, wherein the force device is a power steering device.