JP2020104833A - Vehicle brake apparatus - Google Patents

Abstract

To provide a vehicle brake apparatus which can improve booster responsiveness at braking.SOLUTION: A vehicle brake apparatus comprises: a master cylinder 21 for discharging working fluids; connection paths 61, 62 for connecting the master cylinder 21 and wheel cylinders 71 to 74; master cut valves 501, 502 arranged at the connection paths 61, 62; booster valves 503 to 506 arranged at the connection paths 61, 62 so as to be located at a downstream side rather than the master cut valves 501, 502; branch paths 64, 66 connected to the connection paths 61, 62 between the master cut valves 501, 502 and the booster valves 503 to 506; pumps 511, 512 for discharging the working fluids to the branch paths 64, 66; and a control device 8 for controlling the master cut valves 501, 502, the booster valves 503 to 506 and the pumps 511, 512. Only the booster valves 503 to 506 are arranged between the pumps 511, 512 and the wheel cylinders 71 to 74.SELECTED DRAWING: Figure 1

Description

The present invention relates to a vehicle braking device.

Conventionally, for example, a vehicle braking device disclosed in Patent Document 1 below is known. In this conventional vehicle brake system, a cutoff valve, which is a solenoid valve, is provided on a connection path that connects a pressure source for discharging hydraulic fluid and a pressure increasing valve for increasing the pressure of a wheel cylinder. The cutoff valve is controlled to be open in normal times.

US Patent No. 9315180

By the way, in a solenoid valve such as a cut-off valve, the flow passage of the hydraulic fluid is generally narrowed, and it may act as a so-called orifice. Therefore, in a vehicle braking device, for example, in a situation where high responsiveness is required such as during emergency braking, pressure loss due to orifices occurs as the number of solenoid valves increases, and there is room for improving boost responsiveness. ..

The present invention has been made to solve the above problems. That is, an object of the present invention is to provide a vehicle braking device capable of improving the boosting responsiveness during braking.

In order to solve the above-mentioned problems, the vehicle braking device according to the present invention includes a first supply unit that discharges hydraulic fluid and a first supply unit that supplies the hydraulic fluid discharged from the first supply unit to a wheel cylinder. A connecting path connecting the supply unit and the wheel cylinder, a shutoff valve provided in the connecting path, a pressure increasing valve provided between the shutoff valve of the connecting path and the wheel cylinder, a shutoff valve of the connecting path and a pressure increasing valve And a second supply portion for discharging the working fluid to the branch passage so as to supply the working fluid to the wheel cylinder via the connection passage and the branch passage, a shutoff valve, and a pressure increasing valve. , A second supply unit, which normally closes the shutoff valve and opens the pressure increasing valve to cause the second supply unit to discharge the working fluid to the branch passage. Has a control unit that opens the shut-off valve and opens the pressure increasing valve in an abnormal condition where the hydraulic fluid cannot be discharged to the branch passage, and only the pressure increasing valve is arranged between the second supply unit and the wheel cylinder. ..

According to this, as compared with the case where another solenoid valve or the like is provided between the second supply unit and the wheel cylinder in addition to the pressure increasing valve, when the hydraulic fluid is supplied from the second supply unit to the wheel cylinder. The pressure loss due to the orifice can be reduced. Therefore, the vehicle braking device can improve the boosting responsiveness during braking.

It is a schematic diagram showing the composition of the braking device for vehicles concerning an embodiment. It is a schematic diagram showing the composition of the braking control device for vehicles concerning the 1st modification. It is a schematic diagram showing the composition of the braking control device for vehicles concerning the 2nd modification. It is a schematic diagram showing the composition of the braking control device for vehicles concerning the 2nd modification.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments and modifications, the same or equivalent portions are designated by the same reference numerals in the drawings. Further, each drawing used for the description is a schematic view, and the shape of each part may not necessarily be strict.

As shown in FIG. 1, the vehicle braking device 1 includes a cylinder mechanism 2, a reservoir tank 3, a stroke simulator 4, a hydraulic pressure control mechanism 5, a hydraulic circuit 6 that connects respective members with a flow path, and a wheel. A cylinder 7 and a control device 8 as a control unit are provided. The hydraulic control mechanism 5 is provided with various solenoid valves described below, and its operation is controlled by the control device 8. The wheel cylinder 7 is provided on the left rear wheel RL of the vehicle, the wheel cylinder 71 provided on the right front wheel FR, the wheel cylinder 73 provided on the left front wheel FL, and the right rear wheel RR. Wheel cylinder 74.

The cylinder mechanism 2 includes a master cylinder 21 as a first supply unit, master pistons 22 and 23 that are driven according to an operation of a brake operating member 28 by a driver, master chambers 24 and 25, a stroke sensor 26, and a pressure sensor. And a sensor 27. The master pistons 22 and 23 partition the master chambers 24 and 25 in the master cylinder 21. The hydraulic pressure in the master chambers 24, 25 (hereinafter referred to as “master pressure”) increases as the master pistons 22, 23 advance. The operation amount of the brake operation member 28 (hereinafter, also referred to as “stroke amount”) is detected by the stroke sensor 26. Further, the master pressure that changes with the operation of the brake operating member 28 is detected by the pressure sensor 27. The stroke sensor 26 and the pressure sensor 27 output the detected stroke amount and master pressure to the control device 8. The master pistons 22 and 23 are urged toward their initial positions by springs (not shown).

The reservoir tank 3 is a tank (atmospheric pressure) released to the outside air and stores a hydraulic fluid. The reservoir tank 3 is connected by a hydraulic circuit 6 to the master cylinder 21 and a hydraulic control mechanism 5 described in detail later. The flow passages between the reservoir tank 3 and the master chambers 24, 25 communicate with each other when the master pistons 22, 23 are in the initial position, and are shut off when the master pistons 22, 23 advance a predetermined amount.

The stroke simulator 4 is a device that applies a reaction force to the brake operating member 28. The stroke simulator 4 is connected to the master chamber 25 via a simulator cut valve 41. The simulator cut valve 41 is a normally closed electromagnetic valve that is closed when not energized, and is normally opened. The stroke simulator 4 may be connected to the master chamber 24 via the simulator cut valve 41.

The hydraulic pressure control mechanism 5 controls the hydraulic pressure (hereinafter, referred to as “wheel pressure”) of the wheel cylinders 7 (wheel cylinders 71 to 74 provided on each wheel) based on a command from the control device 8. It is a device. The hydraulic pressure control mechanism 5 is provided with two piping systems, a first piping system La and a second piping system Lb, which are formed by a hydraulic circuit 6 having a plurality of passages through which hydraulic fluid can flow. The first piping system La controls the wheel pressure of the wheel cylinder 71 and the wheel cylinder 72, and the second piping system Lb controls the wheel pressure of the wheel cylinder 73 and the wheel cylinder 74. That is, the two piping systems, the first piping system La and the second piping system Lb, have a so-called X piping structure.

The hydraulic control mechanism 5 includes a master cut valve 501 and a master cut valve 502 as cutoff valves in each of the first piping system La and the second piping system Lb. Further, the hydraulic control mechanism 5 includes a pressure increasing valve 503, a pressure increasing valve 504, a pressure increasing valve 505, and an increasing valve for each wheel (wheel cylinders 71 to 74) connected to each of the first piping system La and the second piping system Lb. A pressure valve 506, a pressure reducing valve 507, a pressure reducing valve 508, a pressure reducing valve 509, and a pressure reducing valve 510 are provided. Further, the hydraulic control mechanism 5 includes a pump 511 and a pump 512 as a second supply unit in each of the first piping system La and the second piping system Lb, and a common motor 513 that drives these pumps 511 and 512. Equipped with.

Further, the hydraulic control mechanism 5 includes a linear valve 514 and a linear valve 514 that constitute a pressure adjusting unit that adjusts the hydraulic pressure discharged from the discharge ports of the pumps 511 and 512 in each of the first piping system La and the second piping system Lb. The linear valve 515 is provided with a normally closed valve 516 and a normally closed valve 517 that are arranged in series with the linear valves 514 and 515. Furthermore, the hydraulic control mechanism 5 includes a pressure sensor 518 and a pressure sensor 519 in each of the first piping system La and the second piping system Lb.

The master cut valves 501 and 502 as shutoff valves are normally open solenoid valves that are open when not energized. The master cut valve 501 is provided in a connection path 61 that connects the master chamber 24 of the master cylinder 21, the wheel cylinder 71, and the wheel cylinder 72. The master cut valve 502 is provided in the connection passage 62 that connects the master chamber 25 of the master cylinder 21, the wheel cylinder 73, and the wheel cylinder 74. The master cut valves 501 and 502 shut off the connection paths 61 and 62 as needed. Therefore, when the master cut valves 501 and 502 are closed, the master pressure is not supplied to the wheel cylinders 71 to 74.

The booster valves 503 to 506 are normally open solenoid valves that are open when not energized. The pressure increasing valve 503 is provided in the connection passage 61 on the downstream side of the connection portion between the connection passage 61 and a branch passage 64 described later, and on the upstream side of the wheel cylinder 71. In the following description, the upstream side is the side closer to the master cylinder 21, and the downstream side is the side closer to the wheel cylinders 71-74. Similarly, the pressure increasing valve 504 is provided in the connection passage 61 on the downstream side of the connection portion between the connection passage 61 and the branch passage 64 and on the upstream side of the wheel cylinder 72.

The pressure increasing valve 505 is provided in the connection passage 62 on the downstream side of the connecting portion between the connection passage 62 and the branch passage 66 described later and on the upstream side of the wheel cylinder 73. Similarly, the pressure increasing valve 506 is provided in the connection passage 62 on the downstream side of the connecting portion between the connection passage 62 and the branch passage 66 and on the upstream side of the wheel cylinder 74.

The pressure increase valves 503 to 506 are provided on the downstream side of the master cylinder 21 as the first supply unit or the pumps 511 and 512 as the second supply unit. When the pressure increase valves 503 to 506 are open, the wheel pressure can be increased by supplying the hydraulic fluid from the upstream side of the pressure increase valves 503 to 506. The pressure increasing valves 503 to 506 are provided with check valves that allow only the flow of hydraulic fluid from the wheel cylinders 71 to 74 side to the master cut valves 501 and 502 side.

The pressure reducing valves 507 to 510 are normally closed solenoid valves that are closed when not energized. The pressure reducing valve 507 is provided in the flow path of the hydraulic circuit 6 that connects the wheel cylinder 71 and the reservoir tank 3. The pressure reducing valve 508 is provided in the flow path of the hydraulic circuit 6 that connects the wheel cylinder 72 and the reservoir tank 3. The pressure reducing valve 509 is provided in the flow path of the hydraulic circuit 6 that connects the wheel cylinder 73 and the reservoir tank 3. The pressure reducing valve 510 is provided in the flow path of the hydraulic circuit 6 that connects the wheel cylinder 74 and the reservoir tank 3. The pressure reducing valves 507 to 510 can reduce the wheel pressure by being controlled to the open state.

The pumps 511 and 512 are driven by a common motor 513. The motor 513 is, for example, an electric motor. The pump 511, which is the second supply unit, is provided in the first piping system La. The pump 511 has a suction port 511a as a suction portion and a discharge port 511b. The pump 511 includes a check valve mechanism (not shown) provided in the suction port 511a and the discharge port 511b. The suction port 511 a is directly connected to the reservoir tank 3 via the suction passage 63. Here, “direct” means that no other member is provided between the two members. Therefore, no other member is provided between the pump 511 and the reservoir tank 3. The discharge port 511b is connected to the branch passage 64. The pump 511 can directly suck the working fluid from the reservoir tank 3 via the suction passage 63 connected to the suction port 511a without using other members. Therefore, the pump 511 can quickly suck the working fluid from the reservoir tank 3 as compared with the case where the working fluid is sucked through the master cylinder 21, for example.

The branch path 64 branches from the connection path 61 and is connected to the discharge port 511b of the pump 511. The branch passage 64 is branched from the connection passage 61 on the downstream side of the master cut valve 501 and on the upstream side of the pressure increase valves 503 and 504. As a result, the upstream pump 511 can supply the hydraulic fluid to the wheel cylinders 71 and 72 via the branch passage 64 and the connection passage 61 in which only the pressure increasing valves 503 and 504 are arranged without providing other members. it can. In other words, the pump 511 can supply the hydraulic fluid to the wheel cylinders 71 and 72 by passing only the pressure increasing valves 503 and 504.

The pump 512, which is the second supply unit, is provided in the second piping system Lb. The pump 512 has a suction port 512a as a suction portion and a discharge port 512b. The pump 512 includes a check valve mechanism (not shown) provided in the suction port 512a and the discharge port 512b. The suction port 512 a is connected to the reservoir tank 3 via the suction passage 65. The discharge port 512b is connected to the branch passage 66. As a result, the pump 512 can directly suck the working fluid from the reservoir tank 3 via the suction passage 65 connected to the suction port 512a without using other members. Therefore, the pump 512 can quickly suck the working fluid from the reservoir tank 3 as compared with the case where the working fluid is sucked through the master cylinder 21, for example.

The branch path 66 branches from the connection path 62 and is connected to the discharge port 512b of the pump 512. The branch passage 66 is branched from the connection passage 62 on the downstream side of the master cut valve 502 and on the upstream side of the pressure increase valves 505, 506. As a result, the upstream pump 512 can supply the hydraulic fluid to the wheel cylinders 73 and 74 via the branch passage 66 and the connection passage 62 in which only the pressure increasing valves 505 and 506 are arranged without providing other members. it can. In other words, the pump 512 can supply the hydraulic fluid to the wheel cylinders 73 and 74 by passing only the pressure increasing valves 505 and 506.

The linear valves 514 and 515 that form the pressure adjusting unit are normally open solenoid valves that are open when de-energized, and are differential solenoid valves that are capable of differential pressure control by linear control. The linear valves 514 and 515 adjust the hydraulic pressure of the hydraulic fluid discharged from the discharge ports 511b and 512b of the pumps 511 and 512, respectively. Further, the normally closed valves 516 and 517 that constitute the pressure adjusting unit are normally closed solenoid valves that are closed when not energized.

The linear valve 514 and the normally closed valve 516 are provided in the first piping system La as a pressure adjusting unit. The linear valve 514 and the normally closed valve 516 are provided in the return path 67. The return passage 67 connects the branch passage 64 and the suction port 511a so as to send a part of the hydraulic fluid discharged from the discharge port 511b of the pump 511 to the suction port 511a as a suction portion via the suction passage 63. .. As a result, a part of the hydraulic fluid in the branch passage 64 is returned to the suction passage 63 via the return passage 67 by controlling the normally closed valve 516 to the open state and controlling the differential pressure of the linear valve 514 by the linear control. You can As a result, the hydraulic pressure of the hydraulic fluid discharged from the pump 511 can be adjusted to a desired hydraulic pressure.

The linear valve 515 and the normally closed valve 517 are provided in the second piping system Lb as a pressure adjusting unit. The linear valve 515 and the normally closed valve 517 are provided in the return path 68. The return passage 68 is provided with a branch passage 66 and a suction port 512a so that a part of the hydraulic fluid discharged from the discharge port 512b of the pump 512 is sent (returned) to the suction port 512a which is a suction portion via the suction passage 65. Connect. Thus, the normally closed valve 517 is controlled to be in the open state, and the linear pressure of the linear valve 515 is controlled by the linear control to return a part of the hydraulic fluid in the branch passage 66 to the suction passage 65 via the return passage 68. You can As a result, the hydraulic pressure of the hydraulic fluid discharged from the pump 512 can be adjusted to a desired hydraulic pressure.

Further, by providing the linear valves 514 and 515 forming the pressure adjusting units in each of the first piping system La and the second piping system Lb, the liquid of the hydraulic fluid discharged from the discharge ports 511b and 512b of the pumps 511 and 512 is provided. The pressure can be adjusted independently. This makes it possible to stabilize the behavior and posture of the vehicle during braking.

The pressure sensor 518 detects the hydraulic pressure of the hydraulic fluid discharged from the pump 511, that is, the wheel pressure of the wheel cylinders 71 and 72 in the first piping system La. The pressure sensor 519 detects the hydraulic pressure of the hydraulic fluid discharged from the pump 512, that is, the wheel pressure of the wheel cylinders 73 and 74 in the second piping system Lb. The pressure sensors 518 and 519 output the detected hydraulic pressure (wheel pressure) to the control device 8.

The control device 8 as a control unit is an electronic control unit (microcomputer) having CPU, ROM, RAM, various interfaces, etc. as main components, and based on the information from the various sensors described above, the simulator cut valve 41 and This is a device for controlling the hydraulic pressure control mechanism 5. The control device 8 determines the target deceleration of the vehicle according to the stroke amount of the brake operating member 28, for example, and determines the target wheel pressure based on the target deceleration. Then, the control device 8 controls the electromagnetic valves 41, 501 to 510, 514 to 517 and the motor 513 based on the target wheel pressure. Opening/closing control of each solenoid valve 41, 501-510, 514-517 includes linear control. By controlling the driving of the motor 513, the operations of the pumps 511 and 512 are controlled. The control device 8 controls the operation of each of the solenoid valves 41, 501 to 510, 514 to 517 and the pumps 511 and 512 to increase or decrease the wheel pressure according to, for example, ABS control or TRC control, and the behavior of the vehicle during braking. And stabilize the posture.

Here, the control device 8 closes the master cut valves 501 and 502 and opens the pressure increase valves 503 to 506 in a normal time when the pumps 511 and 512, which are the second supply unit, can supply the hydraulic fluid. .. Then, the control device 8 causes the pumps 511 and 512 to discharge the hydraulic fluid to the branch paths 64 and 66, and brakes the left rear wheel RL, the right front wheel FR, the left front wheel FL, and the right rear wheel RR, respectively. By the way, when it is required to increase the wheel pressure of the wheel cylinders 71 to 74 with high pressurization response, such as during an emergency brake, the wheel cylinders 71 to 74 can be operated without reducing the pressure of the hydraulic fluid boosted by the pumps 511 and 512. It is necessary to feed 74.

As described above, in the vehicle braking device 1, when the pumps 511 and 512 supply the hydraulic fluid whose pressure is increased to the wheel cylinders 71 to 74 via the branch passages 64 and 66 and the connection passages 61 and 62, the hydraulic fluid is Only the pressure increasing valves 503 to 506 flow. Therefore, the hydraulic fluid is supplied to the wheel cylinders 71 to 74 only under the influence of the orifice (throttle) caused by the flow passage diameters of the pressure increasing valves 503 to 506. As a result, compared with the case where electromagnetic valves such as a cut-off valve are further provided between the pumps 511 and 512 and the wheel cylinders 71 to 74, in addition to the pressure increasing valves 503 to 506, the orifice () for receiving the hydraulic fluid is provided. The influence of the diaphragm is small, and as a result, the pressure loss is small. Therefore, the hydraulic fluid (hydraulic pressure) can be promptly supplied (transmitted) from the pumps 511 and 512 to the wheel cylinders 71 to 74, and the pressurization response can be improved.

On the other hand, the control device 8 opens the master cut valves 501 and 502 and opens the pressure increase valves 503 to 506 when the pumps 511 and 512 cannot discharge the hydraulic fluid to the branch passages 64 and 66. In this case, the master pressure corresponding to the operation of the brake operating member 28 is supplied to the wheel cylinders 71 to 74 via the connection paths 61 and 62, so that the left rear wheel RL, the right front wheel FR, the left front wheel FL and The right rear wheel RR is braked.

As can be understood from the above description, the vehicle braking device 1 supplies the master cylinder 21 as a first supply unit that discharges the hydraulic fluid, and the hydraulic fluid discharged from the master cylinder 21 to the wheel cylinders 71 to 74. As described above, the connection paths 61 and 62 connecting the master cylinder 21 and the wheel cylinders 71 to 74, the master cut valves 501 and 502 as the shutoff valves provided in the connection paths 61 and 62, and the connection paths 61 and 62. Of the pressure increasing valves 503 to 506 provided between the master cut valves 501 and 502 and the wheel cylinders 71 to 74, and between the master cut valves 501 and 502 and the pressure increasing valves 503 to 506 of the connection paths 61 and 62. Second supply for discharging the hydraulic fluid to the branch passages 64, 66 so that the hydraulic fluid is supplied to the wheel cylinders 71 to 74 via the branch passages 64, 66, the connection passages 61, 62 and the branch passages 64, 66. Is a control unit that controls the pumps 511 and 512, the master cut valves 501 and 502, the pressure increasing valves 503 to 506, and the pumps 511 and 512, and normally closes the master cut valves 501 and 502. In addition, the master cut valve is opened when the pressure increase valves 503 to 506 are opened to cause the pumps 511 and 512 to discharge the working fluid to the branch passages 64 and 66, and the pumps 511 and 512 cannot discharge the working fluid to the branch passages 64 and 66. The control device 8 as a control unit that opens the valves 501 and 502 and the pressure increase valves 503 to 506 is provided, and only the pressure increase valves 503 to 506 are provided between the pumps 511 and 512 and the wheel cylinders 71 to 74. Are placed.

According to this, as compared with the case where another solenoid valve or the like is provided between the pumps 511 and 512 and the wheel cylinders 71 to 74 in addition to the pressure increasing valves 503 to 506, the pumps 511 and 512 to the wheel cylinders 71 to 512 are provided. It is possible to reduce the pressure loss due to the orifice when supplying the hydraulic fluid to 74. Therefore, the vehicle braking device 1 can improve the boosting responsiveness during braking. Further, since the number of solenoid valves provided in the hydraulic control mechanism 5 can be reduced, the vehicle braking device 1 can be downsized.

Further, the vehicle braking device 1 may include a reservoir tank 3 that stores hydraulic fluid, and suction passages 63 and 65 that directly connect the pumps 511 and 512 to the reservoir tank 3.

According to this, the pumps 511 and 512 can suck the working fluid directly from the reservoir tank 3 through the suction passages 63 and 65 without passing through the master cylinder 21, for example. Thereby, for example, as compared with the case where the hydraulic fluid is sucked through the master cylinder 21, the pumps 511 and 512 quickly suck the hydraulic fluid from the reservoir tank 3, pressurize the hydraulic fluid, and press the wheel cylinders 71 to 74. Can be supplied to. Therefore, the boosting responsiveness during braking can be improved.

Further, the vehicle braking device 1 is configured to send a part of the hydraulic fluid discharged from the pumps 511 and 512 to the suction ports 511a and 512a, which serve as suction portions for the pumps 511 and 512 to suck the hydraulic fluid. 64, 66 and the return ports 67, 68 connecting the suction ports 511a, 512a, and the linear valves 514, 515 and the normally closed valves 516, 517 as pressure regulators provided on the return channels 67, 68. You may prepare.

According to this, the hydraulic pressure of the hydraulic fluid discharged from the discharge ports 511b and 512b of the pumps 511 and 512 to the branch passages 64 and 66 can be adjusted appropriately. As a result, the adjusted hydraulic fluid (hydraulic pressure) can be supplied to the wheel cylinders 71 to 74, and as a result, the boosting responsiveness during braking can be improved.

(First modification)
In the above-described embodiment, the linear valves 514 and 515 forming the pressure regulator are normally open solenoid valves that are open when de-energized. Alternatively, as shown in FIG. 2, normally-closed linear valves 520 and 521 can be used so as to include at least a normally-closed valve that is in a closed state when not energized as a pressure regulating unit. In this case, the linear valves 520 and 521 can shut off the flow of hydraulic fluid. Therefore, when the linear valves 520 and 521 are used as the normally closed valves, the normally closed valves 516 and 517 can be omitted, and the vehicle braking device 1 (more specifically, the hydraulic control mechanism 5) can be miniaturized. Can be achieved. Other effects are similar to those of the above-described embodiment.

(Second modified example)
In the above-described embodiment and the first modification, the suction passage 63 is configured to directly connect the pump 511 and the reservoir tank 3 arranged outside the hydraulic pressure control mechanism 5. Further, in the embodiment and the first modified example, the pump 512 and the external reservoir tank 3 are configured so that the suction passage 65 is directly connected. That is, in the vehicle braking device 1 according to the above-described embodiment and the first modification, the pumps 511 and 512 operate directly from the reservoir tank 3 arranged outside the hydraulic control mechanism 5 via the suction passages 63 and 65. It was configured as a so-called outline type that inhales liquid.

However, the vehicle braking device 1 may not include the suction passages 63 and 65. For example, as shown in FIGS. 3 and 4, the vehicle braking device 1 may include a low pressure reservoir 522 and a low pressure reservoir 523 different from the reservoir tank 3. The pumps 511 and 512 suck the hydraulic fluid from the low pressure reservoirs 522 and 523. In this case, as compared with the case where the pumps 511 and 512 suck the working fluid from the reservoir tank 3 through the inside of the master cylinder 21, the suctionability of the working fluid by the pumps 511 and 512 can be improved. In the following description, in FIG. 3 corresponding to the above embodiment and FIG. 4 corresponding to the first modification, the same parts as those in the embodiment and the first modification are denoted by the same reference numerals, and the description thereof will be omitted. To do.

The low pressure reservoir 522 includes a piston 522b housed inside a cylinder 522a. The piston 522b partitions the inside of the cylinder 522a into a liquid chamber 522c filled with hydraulic fluid and a gas chamber 522d filled with gas. A spring (not shown) that biases the piston 522b toward the gas chamber 522d is housed inside the liquid chamber 522c. The pump 511 is directly connected to the liquid chamber 522c of the low pressure reservoir 522 via the suction passage 63. As a result, the pump 511 sucks the hydraulic fluid from the low pressure reservoir 522.

The low pressure reservoir 523 includes a piston 523b housed inside a cylinder 523a. The piston 523b partitions the inside of the cylinder 523a into a liquid chamber 523c filled with hydraulic fluid and a gas chamber 523d filled with gas. A spring (not shown) for urging the piston 523b toward the gas chamber 523d is housed inside the liquid chamber 523c. The pump 512 is directly connected to the liquid chamber 523c of the low pressure reservoir 523 via the suction passage 65. Accordingly, the pump 512 draws the hydraulic fluid from the low pressure reservoir 523.

In the low pressure reservoirs 522 and 523, the pistons 522b and 523b reduce the volumes of the liquid chambers 522c and 523c against the biasing force of a spring (not shown) due to the negative pressure generated by the operation of the pumps 511 and 512. It works to let you. Accordingly, the pump 511 can suck the hydraulic fluid through the suction passage 63 by operating the piston 522b of the low pressure reservoir 522. Similarly, the pump 512 can suck the hydraulic fluid through the suction passage 65 by operating the piston 523b of the low pressure reservoir 523. In the liquid chamber 522c of the low pressure reservoir 522, sufficient hydraulic fluid for pressurizing the wheel cylinders 71, 74 connected to the first piping system La is stored. Further, the hydraulic pressure 523c of the low pressure reservoir 523 stores sufficient hydraulic fluid for pressurizing the wheel cylinders 72, 73 connected to the second piping system Lb.

In this way, when the vehicle braking device 1 is configured, the same effects as those of the above-described embodiment and the first modification can be expected, and in addition, the vehicle braking device 1 (more specifically, the hydraulic control mechanism 5). It is also possible to reduce the size of the hydraulic circuit 6). As a result, it is possible to improve mountability when the vehicle braking device 1 is mounted on a vehicle.

(Third modification)
In the above embodiment, the flow passage diameters (or orifice diameters) in the flow passages of the pressure boosting valves 503 to 506 are not particularly limited, and are the same, for example. Instead of this, of the pressure increasing valves 504, 505 provided in the connection paths 61, 62 connected to the wheel cylinders 72, 73 as front wheel side wheel cylinders provided in the front wheels of the vehicle, that is, the left front wheel FL and the right front wheel FR. The passage diameters (orifice diameters) are provided in the connection paths 61, 62 connected to the wheel cylinders 71, 74 as the rear wheel side wheel cylinders provided in the rear wheels of the vehicle, that is, the left rear wheel RL and the right rear wheel RR. It is also possible to make the diameter larger than the flow path diameter (orifice diameter) of the pressure increasing valves 503 and 506. As a result, the hydraulic fluid discharged from the pumps 511 and 512 can flow through the flow passage having a large flow passage diameter (orifice diameter) in the pressure increase valves 504 and 505. As a result, the pressure loss due to the orifice is reduced, and in particular, it is possible to improve the boosting responsiveness in the wheel cylinders 72, 73 that are the front wheel cylinders. Therefore, the vehicle braking device 1 can stabilize the behavior during braking of the vehicle.

The present invention is not limited to the above embodiment, and various modifications can be made without departing from the object of the present invention.

For example, in the above-mentioned embodiment and each modification, the vehicle braking device 1 is applied to a four-wheel vehicle including four wheels, that is, the left front wheel FL, the right front wheel FR, the left rear wheel RL, and the right rear wheel RR. I did it. Alternatively, the vehicle braking device 1 can be applied to a two-wheel vehicle including front wheels and rear wheels, a three-wheel vehicle including front wheels and left and right rear wheels, or a vehicle including five or more wheels. ..

Further, in the embodiment and the first modified example, as shown in FIGS. 1 and 2, the hydraulic control mechanism 5 has a so-called X piping configuration. However, as for the piping configuration of the hydraulic control mechanism 5, as shown in FIGS. 3 and 4 in the second modified example, the first piping system La includes the wheel cylinders 72, 73 of the right front wheel FR and the left front wheel FL, that is, A so-called front-rear piping that controls the wheel pressure on the front wheel side and the second piping system Lb controls the wheel cylinders 71, 74 of the left rear wheel RL and the right rear wheel RR, that is, the wheel pressure on the rear wheel side. It is also possible to do so. In this way, when the front and rear pipes are adopted, regenerative braking can be performed on the front wheel side when braking a hybrid vehicle or the like.

DESCRIPTION OF SYMBOLS 1... Vehicle braking device, 2... Cylinder mechanism, 21... Master cylinder (first supply unit), 22, 23... Master piston, 24, 25... Master chamber, 26... Stroke sensor, 27... Pressure sensor, 28... Brake Operation member, 3... Reservoir tank, 4... Stroke simulator, 41... Simulator cut valve, 5... Liquid pressure control mechanism, 501, 502... Master cut valve (shutoff valve), 503-506... Pressure increasing valve, 507-510... Decompression Valves, 511, 512... Pump (second supply part), 511a, 512a... Suction port (suction part), 511b, 512b... Discharge port, 513... Motor, 514, 515... Linear valve (pressure adjusting part), 516, 517... Normally closed valve (pressure regulating section), 518, 519... Pressure sensor, 520, 521... Linear valve (pressure regulating section), 522, 523... Low pressure reservoir (reservoir tank), 522a, 523a... Cylinder, 522b, 523b ... Pistons, 522c, 523c... Liquid chambers, 522d, 523d... Gas chambers, 6... Hydraulic circuits, 61, 62... Connection passages, 63, 65... Suction passages, 64, 66... Branch passages, 67, 68... Return passages , 7... Wheel cylinder, 71-74... Wheel cylinder, 8... Control device (control unit), FL... Left front wheel, FR... Right front wheel, RL... Left rear wheel, RR... Right rear wheel, La... First piping system , Lb... Second piping system

Claims (7)

A first supply unit for discharging the hydraulic fluid,
A connection path connecting the first supply unit and the wheel cylinder so as to supply the hydraulic fluid discharged from the first supply unit to the wheel cylinder,
A shutoff valve provided in the connection path,
A pressure increasing valve provided between the shutoff valve and the wheel cylinder of the connection path,
A branch path that branches from between the shutoff valve and the pressure increasing valve of the connection path;
A second supply unit configured to discharge the hydraulic fluid to the branch passage so as to supply the hydraulic fluid to the wheel cylinder via the connection passage and the branch passage,
A control unit that controls the shutoff valve, the pressure increasing valve, and the second supply unit, and normally closes the shutoff valve and opens the pressure increasing valve to the second supply unit. The control unit that discharges the hydraulic fluid to the branch passage and opens the shut-off valve and the pressure increasing valve when the second supply unit cannot discharge the hydraulic fluid to the branch passage in an abnormal condition, Prepare,
A vehicle braking device in which only the pressure increasing valve is disposed between the second supply unit and the wheel cylinder. A reservoir tank for storing the hydraulic fluid,
The vehicle braking device according to claim 1, further comprising: an intake passage that directly connects the second supply unit and the reservoir tank. A return passage connecting the branch passage and the suction portion so that a part of the working fluid discharged from the second supply portion is sent to the suction portion for sucking the working fluid by the second supply portion. ,
The vehicle braking device according to claim 1 or 2, further comprising: a pressure adjusting unit provided on the return path. The pressure regulator is
The vehicle braking device according to claim 3, comprising at least a normally closed valve. The wheel cylinder includes a front wheel side wheel cylinder provided on a front wheel of the vehicle and a rear wheel side wheel cylinder provided on a rear wheel of the vehicle,
The flow passage diameter of the pressure increasing valve provided in the connection passage connected to the front wheel side wheel cylinder is larger than the flow passage diameter of the pressure increasing valve provided in the connection passage connected to the rear wheel side wheel cylinder. The vehicle braking device according to any one of claims 1 to 4. The second supply unit is a pump that pressurizes and discharges the hydraulic fluid,
The vehicle according to any one of claims 1 to 5, wherein the pump supplies the pressurized hydraulic fluid to each of two piping systems that supply the hydraulic fluid to the wheel cylinder. Braking device. The vehicle braking device according to claim 2, wherein the reservoir tank is a low-pressure reservoir having a piston operated by negative pressure.

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