JP2005313705A - Device for generating vehicular brake hydraulic pressure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for generating vehicular brake hydraulic pressure equipped with a master cylinder and a stroke simulator, provided with a communication controlling means with high durability, and inexpensively structured. <P>SOLUTION: The device comprises a first piston (MP1) interlocking to a brake operating member (BP), a second piston (MP2), and the stroke simulator (AB) absorbing fluid amount according to output hydraulic pressure of a first master hydraulic pressure chamber (C1) and adding a stroke to the first piston. By the communication controlling means equipped with a seal member (S5) disposed on a cylinder housing and a communicating hole (P8) formed in a direction intersecting a center axis of the second piston, when the second piston is at an initial position, the master hydraulic pressure chamber and the stroke simulator are communicated through the communicating hole. When the second piston moves forward from the initial position by not less than a predetermined distance, communication between the first master hydraulic pressure chamber and the stroke simulator is intercepted. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a vehicular brake hydraulic pressure generator, and more particularly to a vehicular brake hydraulic pressure generator equipped with a stroke simulator.

  Various types of vehicle brake hydraulic pressure generators equipped with a stroke simulator are known. Usually, a hydraulic pressure source including a hydraulic pressure source is used to control the hydraulic pressure source according to the operation of the brake operating member. Regulates the hydraulic pressure and supplies it to the wheel cylinder, shuts off the communication between the master cylinder and the wheel cylinder, and connects the master cylinder to the wheel cylinder when the hydraulic pressure control means is abnormal. The hydraulic pressure according to the operating force of the brake operating member is supplied to the wheel cylinder.

  The first master liquid is slidably accommodated in the cylinder housing and moved back and forth in conjunction with the brake operation member, and the first piston is slidably accommodated in the cylinder housing. A pressure chamber is formed, and a second piston that forms a second master hydraulic pressure chamber between the pressure chamber and the cylinder housing communicates with the first master hydraulic pressure chamber in accordance with an output hydraulic pressure of the first master hydraulic pressure chamber. A stroke simulator that absorbs the fluid volume and applies a stroke corresponding to the operating force of the brake operating member to the first piston, and the first master hydraulic chamber is in communication with the first master hydraulic chamber. When the second piston is in the initial position, the first master hydraulic chamber communicates with the stroke simulator, and the second piston is in the initial position. When moving forward Luo predetermined distance or more, those with communication control means are known to block the communication between the first master chamber and the stroke simulator.

  Said communication control means is disclosed as a 3rd valve apparatus in the actuator for electrohydraulic brake apparatuses of patent document 1, for example. That is, Patent Document 1 discloses a third valve device including a packing sleeve (corresponding to a seal member) and a hydraulic coupling portion (corresponding to a communication hole for communicating the first master hydraulic chamber with the stroke simulator). It is understood that the third valve device is configured to block communication between the first master hydraulic chamber and the stroke simulator in accordance with the operation of the master piston.

German Patent Publication DE10119128A1

  However, as described in the above-mentioned Patent Document 1, in the case where the seal member disposed on the second piston is used as the communication control means, the communication between the first master hydraulic chamber and the stroke simulator is interrupted. The seal member slides in the cylinder housing. For this reason, when forming the inner peripheral surface of a cylinder housing, since a highly accurate process is requested | required, it becomes an expensive apparatus.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a vehicular brake hydraulic pressure generator having a master cylinder and a stroke simulator, which has a highly reliable communication control means and can be configured at low cost. .

  In order to achieve the above object, the present invention provides a first piston that is slidably accommodated in a cylinder housing and moves back and forth in conjunction with a brake operation member, and the cylinder housing. A second piston that is slidably received in the first piston and forms a first master hydraulic chamber with the first piston, and a second master hydraulic chamber with the cylinder housing; The first master hydraulic chamber communicates with the first master hydraulic chamber, absorbs the amount of fluid corresponding to the output hydraulic pressure of the first master hydraulic chamber, and applies a stroke corresponding to the operating force of the brake operating member to the first piston. A stroke simulator, and a seal member on which the hydraulic pressure of the first master hydraulic chamber acts in a state where the first master hydraulic chamber and the stroke simulator communicate with each other. When in the position, the first master hydraulic pressure chamber communicates with the stroke simulator, and when the second piston moves forward a predetermined distance or more from the initial position, the seal member causes the first master hydraulic pressure chamber to In the vehicular brake hydraulic pressure generator having communication control means for blocking communication with the stroke simulator, the seal member is disposed in the cylinder housing, and the communication control means is arranged on a central axis of the second piston. A communication hole formed in a direction intersecting the first piston, and when the second piston is in an initial position, the first master hydraulic chamber and the stroke simulator are communicated with each other via the communication hole, and the second piston Is moved forward from the initial position by a predetermined distance or more, the communication hole causes the communication hole to be moved to the first master by the seal member. Isolated from chamber, which is constituted so as to block the communication between the stroke simulator and the first master chamber.

  In the vehicle brake fluid pressure generating device, the stroke simulator may be configured to be accommodated in the second piston as described in claim 2.

  Since this invention is comprised as mentioned above, there exist the following effects. That is, in the apparatus according to claim 1, the second piston is provided by a communication control means having a seal member disposed in the cylinder housing and a communication hole formed in a direction intersecting with the central axis of the second piston. Is in the initial position, the first master hydraulic pressure chamber communicates with the stroke simulator through the communication hole, and when the second piston moves forward from the initial position by a predetermined distance or more, the first communication hole is defined by the seal member. Since it is isolated from the master hydraulic chamber and the communication between the first master hydraulic chamber and the stroke simulator can be cut off, high-precision machining is not required when machining the inner peripheral surface of the cylinder housing. Instead, when forming the outer peripheral surface of the second piston, high-precision processing is required, but it is easier and cheaper than the processing of the inner peripheral surface of the cylinder housing.

  Further, the sealing member having the shut-off function is configured such that the hydraulic pressure of the first master hydraulic pressure chamber acts in a state where the first master hydraulic pressure chamber and the stroke simulator communicate with each other, and the brake operation by the driver is performed. When the hydraulic pressure is generated in the first master hydraulic pressure chamber in accordance with the operation of the first piston in response to this, the hydraulic pressure is applied to the sealing member, so that the sealing function of the sealing member is impaired. Even if the situation occurs, the driver can feel it when the hydraulic pressure source or the like is normal, and the reliability as the communication control means is high.

  Furthermore, if the said stroke simulator is set as the structure accommodated in a 2nd piston as described in Claim 2, it can be set as a compact apparatus.

  Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the vehicular brake hydraulic pressure generator according to this embodiment includes a master piston MP1, which is a first piston of the present invention, slidably accommodated in a cylinder housing HS (hereinafter simply referred to as a housing HS). And connected to a brake pedal BP as a brake operation member. Further, the master piston MP2 as the second piston of the present invention is slidably accommodated in the housing HS, and a first master hydraulic chamber C1 is formed between the master piston MP1 and the front end of the housing HS. A second master hydraulic chamber C2 is formed between the two. The first master hydraulic chamber C1 communicates with a stroke simulator AB that absorbs the amount of fluid corresponding to the output hydraulic pressure and applies a stroke corresponding to the operating force of the brake pedal BP to the master piston MP1. It is arranged.

  The housing HS is a bottomed cylindrical body whose front (left side in FIG. 1) is closed, and is formed with a recess B1, a small diameter hole B2, a (stepped) large diameter hole B3, a small diameter hole B4, and a large diameter hole B5. A cylinder hole (cylinder bore) made up of stepped holes is formed, and a screw groove is formed on the inner surface of the rear opening end B6. An annular groove for accommodating the annular seal members S1 to S6 having a cup-shaped cross section is formed on the inner surface of the cylinder hole. An atmospheric pressure chamber C3 is formed between the seal members S1 and S2, and the seal An atmospheric pressure chamber C4 is formed between the members S3 and S4, and an atmospheric pressure chamber C5 is further formed between the sealing members S5 and S6. In addition, since these annular grooves and large-diameter holes B3 can be formed by boring along the axis of the housing HS, the housing HS can be constituted by a single metal part.

  Further, on the side surface of the housing HS, ports P0 and P1 that open before and after the seal members S5 and S6 in the large-diameter hole B3, a port P2 that opens to the second master hydraulic chamber C2 of the recess B1, and atmospheric pressure A port P3 that opens to the chamber C3, a port P4 that opens to the atmospheric pressure chamber C4, and a port P7 that opens to the atmospheric pressure chamber C5 are formed. The ports P3, P4, and P7 are referred to as an atmospheric pressure reservoir RS (hereinafter simply referred to as an “air pressure reservoir RS”). (Reservoir RS).

  On the other hand, the master piston MP1 has a recessed portion M1 that opens forward, and a shaft portion RD that extends rearward. A port P5 that opens to the recessed portion M1 is formed on the side surface of the master piston MP1. . Further, the master piston MP2 has a recess M2 that opens forward, and a communication hole P8 in a direction (offset radial direction) that intersects the central axis of the master piston MP2. Furthermore, a port P6 that opens to the recess M2 is also formed on the side surface of the master piston MP2. Thus, when the master piston MP2 is in the initial position, as shown in FIG. 1, the seal members S5 and S6 are in contact with the outer peripheral surface of the portion where the communication hole P8 is not formed. P8 is formed so as to open before and after the seal members S5 and S6 along the central axis.

  As shown in FIG. 1, a compression spring E1 functioning as a return spring is mounted between the master pistons MP1 and MP2 via a retainer RT, and the return spring is also provided in the recess M2 of the master piston MP2. A compression spring E2 is stored.

  As shown in FIG. 1, the communication hole P8 is formed in a direction inclined at a constant angle with respect to the central axis of the master piston MP2, whereby a communication hole in a direction intersecting with the central axis is formed. Is formed. On the other hand, as shown in FIG. 3, a pair of holes P8a and P8b are formed in the radial direction orthogonal to the central axis of the master piston MP2, and the holes are formed along the central axis so as to communicate with each other. P8c may be formed, and the opening of the hole P8c may be closed by the plug PL. That is, these holes P8a, P8b, and P8c constitute a communication hole that substantially intersects the central axis of the master piston MP2, and can perform the same function as the communication hole P8 of FIG. In FIG. 3, the master piston MP2 has a recess M3, which is provided for convenience in processing the hole P8c, and a plug PL is inserted from the recess M3 into the opening of the hole P8c. .

  Furthermore, in this embodiment, as shown in FIG. 1, the amount of fluid corresponding to the output fluid pressure of the first master fluid pressure chamber C1 is absorbed, and the operating force of the brake pedal BP is applied to the master piston MP1 (first piston). There is provided a stroke simulator AB for applying a stroke according to the above. The sealing member S5 having the above-described blocking function disposed in the large-diameter hole B3 of the housing HS and the communication hole P8 formed so as to open behind the sealing member S5 when the master piston MP2 is in the initial position. Thus, the absorption operation and non-operation of the stroke simulator AB are selectively switched.

  In the stroke simulator AB, a piston member AP is accommodated in a cylinder-shaped housing AH via a seal member S7 so as to be fluid-tightly slidable, and a simulator hydraulic chamber C6 (hereinafter simply referred to as hydraulic pressure) is interposed via the piston member AP. Chamber C6) and simulator atmospheric pressure chamber C7 (hereinafter simply referred to as atmospheric pressure chamber C7) are formed, and the piston member AP is moved to the hydraulic pressure chamber C6 side by the compression spring E3 which is an elastic member housed in the atmospheric pressure chamber C7. (That is, in the direction of reducing the hydraulic pressure chamber C6). Further, a port P9 that communicates with the annular space between the seal members S2 and S6 via the port P0 is formed in the housing AH, and a port P10 that opens the atmospheric pressure chamber C7 to the atmosphere is formed.

  The parts of the master cylinder configured as described above will be described along with an assembly procedure example. First, seal members S1 to S6 are mounted in the annular groove of the housing HS. Next, the compression spring E2 is accommodated in the recess B1 of the housing HS and the recess M2 of the master piston MP2, and the master piston MP2 is accommodated in the cylinder hole through the seal members S1 and S2 so as to be liquid-tightly slidable. Thus, a second master hydraulic chamber C2 is formed in front of the master piston MP2. Then, in a state where the compression spring E1 is stretched through the retainer RT in the recess M1 of the master piston MP1, the liquid is slidably accommodated in the cylinder hole through the seal members S3 and S4. The first master hydraulic chamber C1 is formed between the master piston MP1 and the master piston MP2. In this state, a nut-shaped stopper NH having a screw groove formed on the outer peripheral surface is screwed into the opening end B6 of the housing HS, and the backward movement of the master pistons MP1 and MP2 due to the urging force of the compression spring E2 is prevented. The

  The first master hydraulic chamber C1 and the second master hydraulic chamber C2 formed as described above communicate with the port cylinders WC1 and WC2 of FIG. 2 from the ports P1 and P2 via the hydraulic systems H1 and H2, respectively. It is configured to. When the master pistons MP1 and MP2 are at the initial positions shown in FIG. 1, the first master hydraulic chamber C1 and the second master hydraulic chamber C2 communicate with the atmospheric pressure chambers C4 and C3 via the ports P5 and P6. As a result, it communicates with the reservoir RS via the ports P4 and P3.

  When the master piston MP2 is in the initial position shown in FIG. 1, the seal members S5 and S6 are in contact with the outer peripheral surface of the portion where the communication hole P8 is not formed, and the first master liquid under atmospheric pressure The pressure chamber C1 communicates with the hydraulic chamber C6 of the stroke simulator AB through the communication hole P8 (and ports P0 and P9). When the master piston MP2 moves forward from the initial position by the first stroke d1 (port idle amount) or more, the opening of the port P6 is shielded by the seal member S1, and the second master hydraulic chamber C2 and the atmospheric pressure chamber C3. Communication with is interrupted. Similarly, when the master piston MP1 moves forward from the initial position by the first stroke d1 (port idle) or more, the opening of the port P5 is shielded by the seal member S3, and the first master hydraulic chamber C1 and the atmospheric pressure chamber C4. Communication with is interrupted.

  As the master piston MP1 moves forward, the piston member AP is pushed against the biasing force of the compression spring E3, and a stroke is applied to the master piston MP1. Until the master piston MP2 moves a predetermined distance (second stroke d2) from the initial position and the entire circumference including the opening of the communication hole P8 contacts the seal member S5, the communication hole P8 (and ports P0 and P9) is moved. The hydraulic pressure chamber C6 communicates with the first master hydraulic pressure chamber C1 through the stroke simulator AB. When the master piston MP2 moves forward by a predetermined distance (second stroke d2) from the initial position, the communication hole P8 is isolated from the first master hydraulic chamber C1 by the seal member S5, and the first master hydraulic chamber is obtained. Communication between C1 and hydraulic chamber C6 is blocked.

  Thus, in the present embodiment, the communication control means of the present invention is constituted by the communication hole P8 and the seal member S5 of FIG. In the present embodiment, the interval (axial distance) between the seal members S5 and S6 may be set shorter than that in FIG. 1, for example, by the full stroke of the master piston MP2, the communication hole P8 in FIG. It is good also as comprising so that an upper part may pass seal member S6. Alternatively, after the upper part of the communication hole P8 in FIG. 1 passes through the seal member S6, the lower part of the communication hole P8 in FIG. 1 may pass through the seal member S2. The interval (axial distance) can be made shorter than that in FIG.

  The vehicle brake hydraulic pressure generator configured as described above is connected as shown in FIG. 2 to form a vehicle hydraulic brake device. In FIG. 2, a normally-open electromagnetic on-off valve NO1 is interposed in the hydraulic system H1, and connected to a system of wheel cylinders (typically represented by WC1) via the electromagnetic on-off valve NO1 and operated. A hydraulic pressure source PG that generates and outputs a predetermined hydraulic pressure regardless of the person's brake operation is connected. Similarly, a normally open electromagnetic on-off valve NO2 is interposed in the hydraulic system H2, and connected to a wheel cylinder of another system (typically represented by WC2) through this electromagnetic on-off valve NO2. A hydraulic pressure source PG is connected.

  The hydraulic pressure source PG includes an electric motor M controlled by the electronic control unit ECU, and a hydraulic pump HP driven by the electric motor M. The input side is connected to the reservoir RS, and the output side is connected to the accumulator AC. Communication connection is established. In the present embodiment, the pressure sensor Sps is connected to the output side, and the detected pressure of the pressure sensor Sps is monitored by the electronic control unit ECU. Based on this monitoring result, the electric motor M is controlled by the electronic control unit ECU so that the hydraulic pressure of the accumulator AC is maintained at a pressure between a predetermined upper limit value and a lower limit value.

  An accumulator AC is connected between the electromagnetic on-off valve NO1 of the hydraulic system H1 and the wheel cylinder WC1 via a normally closed first proportional electromagnetic valve SV1, and the output hydraulic pressure of the hydraulic pressure source PG is The pressure is adjusted and supplied to the wheel cylinder WC1. Further, the electromagnetic on-off valve NO1 and the wheel cylinder WC1 are connected to the reservoir RS via a normally closed second proportional electromagnetic valve SV2, so that the hydraulic pressure of the wheel cylinder WC1 is reduced and regulated. It is configured. Similarly, an accumulator AC is connected between the electromagnetic on-off valve NO2 of the hydraulic system H2 and the wheel cylinder WC2 via a normally-closed first proportional solenoid valve SV3, and the output hydraulic pressure of the hydraulic pressure source PG. Is regulated and supplied to the wheel cylinder WC2. Further, the electromagnetic on-off valve NO2 and the wheel cylinder WC2 are connected to the reservoir RS via a normally closed second proportional electromagnetic valve SV4 so that the hydraulic pressure of the wheel cylinder WC2 is reduced and regulated. It is configured. Thus, the hydraulic pressure control means PC is constituted by the hydraulic pressure source PG, the first proportional solenoid valves SV1 and SV3, the second proportional solenoid valves SV2 and SV4, the electronic control unit ECU, the following sensors, and the like.

  In the present embodiment, for example, the pressure sensor Smc is connected to the upstream side of the electromagnetic on-off valve NO2 in the hydraulic system H2, and the pressure sensor Swc is connected to the downstream side and the downstream side of the electromagnetic on-off valve NO1 in the hydraulic system H1. It is connected. The brake pedal BP is provided with a stroke sensor BS for detecting the stroke, and these detection signals are input to the electronic control unit ECU. By these sensors, the output hydraulic pressure of the second master hydraulic chamber C2, the brake hydraulic pressure of the wheel cylinders WC2 and WC1, and the stroke of the brake pedal BP are monitored (the pressure sensor Smc is on the hydraulic system H1 side). Or may be provided in both hydraulic systems). Further, sensors (typically represented by SN) such as wheel speed sensors and acceleration sensors used for various controls such as anti-lock control are provided, and these detection signals are also input to the electronic control unit ECU. It is configured.

  The overall operation of the hydraulic brake device including the vehicle brake hydraulic pressure generator of the present embodiment having the above-described configuration will be described. First, when the hydraulic pressure control means PC is normal, the electromagnetic on-off valves NO1 and NO2 in FIG. 2 are turned on to shut off the hydraulic pressure systems H1 and H2, and the brake operation amount is based on the detected values of the stroke sensor BS and the pressure sensor Smc. The hydraulic pressure corresponding to is supplied from the hydraulic pressure source PG to the wheel cylinders WC1 and WC2. That is, the output current to the first proportional solenoid valves SV1 and SV3 and the second proportional solenoid valves SV2 and SV4 is appropriately controlled so that the wheel cylinder hydraulic pressure detected by the pressure sensor Swc becomes the target wheel cylinder hydraulic pressure. Is done. Thus, the hydraulic pressure corresponding to the operation of the brake pedal BP is supplied to the wheel cylinders WC1 and WC2 by the hydraulic pressure control means PC.

  In this case, the master piston MP2 (second piston) only moves forward by approximately the port idle amount (first stroke d1), and the communication between the second master hydraulic chamber C2 and the atmospheric pressure chamber C3 is blocked. After that, the master piston MP1 (first piston) hardly moves forward, and only the master piston MP1 (first piston) moves forward. At this time, since the first master hydraulic chamber C1 and the hydraulic chamber C6 communicate with each other through the communication hole P8, the brake fluid applied to the piston member AP of the stroke simulator AB according to the operation of the brake pedal BP. When the force due to the pressure becomes equal to or greater than the attachment load of the compression spring E3, the compression spring E3 is compressed and a stroke corresponding to the brake operation force is generated in the master piston MP1.

  On the other hand, when an abnormality occurs in the hydraulic pressure control means PC such as the hydraulic pressure source PG, the electromagnetic on-off valves NO1 and NO2 are de-energized (OFF) to the open position, as shown in FIG. The systems H1 and H2 are in communication. In addition, the first proportional solenoid valves SV1 and SV3 and the second proportional solenoid valves SV2 and SV4 are also de-energized (OFF) to the closed position, and the hydraulic pressure from the hydraulic pressure source PG is applied to the wheel cylinders WC1 and WC2. Is not supplied. When the brake pedal BP is operated in this state and the master piston MP2 moves forward by a predetermined distance (second stroke d2) or more, the entire circumference including the opening of the communication hole P8 comes into contact with the seal member S5, and the first master hydraulic pressure The communication between the chamber C1 and the hydraulic chamber C6 of the stroke simulator AB is cut off, the stroke simulator AB does not operate, and the master piston MP1 (first piston) and the master piston MP2 (second piston) move forward, respectively. The first master hydraulic chamber C1 and the second master hydraulic chamber C2 are compressed. Thus, the hydraulic pressure is output to the hydraulic pressure systems H1 and H2 according to the operation of the brake pedal BP.

  Further, the seal member S5 is configured so that the hydraulic pressure in the first master hydraulic chamber C1 acts even when the first master hydraulic chamber C1 and the stroke simulator AB are in communication with each other. When a hydraulic pressure is generated in the first master hydraulic chamber C1 with the operation of the corresponding master piston MP1 (first piston), this hydraulic pressure is applied to the seal member S5. Therefore, even when the hydraulic pressure source PG or the like is normal, if the sealing function of the sealing member S5 is impaired, the driver does not generate a reaction force even when the brake operation is performed, so the sealing function is impaired. You can experience that.

  FIG. 4 shows another embodiment of the present invention, in which a stroke simulator AB2 is accommodated in a master piston MP2 (second piston). In this embodiment, the seal member S6 is not provided, and a communication hole P11 is formed instead of the communication hole P8 in FIG. The other configuration is the same as that of the embodiment of FIG. 1, and substantially the same components as those of FIG. 1 are denoted by the same reference numerals and arranged in the same manner as FIG. 2. In the stroke simulator AB2 of this embodiment, the piston member AP2 is fluid-tightly slid through a seal member S8 in a cylinder hole formed in the housing MA of the master piston MP2 so as to open rearward through a partition wall MA1. It is accommodated movably and is configured to be urged rearward by a compression spring E4 as an elastic member. The rear end portion of the housing MA is sealed by a plug member MA2 via a seal member S9, and a simulator hydraulic chamber C8 (hereinafter simply referred to as a hydraulic chamber C8) is formed between the plug member MA2 and the piston member AP2. In addition, a simulator atmospheric pressure chamber C9 (hereinafter simply referred to as an atmospheric pressure chamber C9) is formed in front of the piston member AP2.

  In the present embodiment, a communication hole P11 is formed in the housing MA of the master piston MP2, and the master piston MP2 is disposed so that the first hydraulic chamber C1 and the hydraulic chamber C8 communicate with each other at the initial position. Yes. Further, a port P12 that communicates the atmospheric pressure chamber C3 with the atmospheric pressure chamber C9 is formed on the side surface of the housing MA.

  Thus, when the master piston MP2 is in the initial position shown in FIG. 4, the seal member S5 is in contact with the outer peripheral surface of the portion where the communication hole P11 is not formed, and the first master liquid under atmospheric pressure is in contact. The pressure chamber C1 communicates with the hydraulic chamber C8 through the communication hole P11. When the master piston MP2 moves forward from the initial position by the first stroke d1 (port idle amount) or more, the opening of the port P6 is shielded by the seal member S1, and the second master hydraulic chamber C2 and the atmospheric pressure chamber C3. (However, the atmospheric pressure chamber C9 is always in communication with the atmospheric pressure chamber C3 and thus the reservoir RS). Similarly, when the master piston MP1 moves forward from the initial position by the first stroke d1 (port idle) or more, the opening of the port P5 is shielded by the seal member S3, and the first master hydraulic chamber C1 and the atmospheric pressure chamber C4. Communication with is interrupted.

  As the master piston MP1 moves forward, the piston member AP2 is pushed against the biasing force of the compression spring E4, and a stroke is applied to the master piston MP1. Until the master piston MP2 moves from the initial position by a predetermined distance (second stroke d2) and the entire circumference including the opening of the communication hole P11 contacts the seal member S5, the hydraulic chamber C8 is connected via the communication hole P11. The piston member AP2 and the like communicate with the first master hydraulic chamber C1 and function as a stroke simulator. When the master piston MP2 moves forward from the initial position by a predetermined distance (second stroke d2) or more, the communication hole P11 is isolated from the first master hydraulic chamber C1 by the seal member S5, and the first master hydraulic chamber. Communication between C1 and hydraulic chamber C8 is blocked.

  Accordingly, also in this embodiment, when the hydraulic pressure control means PC shown in FIG. 2 is normal, the on-off valves NO1 and NO2 are closed and the hydraulic systems H1 and H2 are closed, so that the master piston MP2 is the first The master piston MP1 only moves forward, and the piston member AP2 or the like operates as a stroke simulator. When the hydraulic pressure control means PC is abnormal, the on-off valves NO1 and NO2 are in the open position, and the hydraulic pressure systems H1 and H2 are opened, so that the master pistons MP1 and MP2 move substantially evenly and the master piston MP2 is in the initial position. From the first master hydraulic pressure chamber C1 and the hydraulic pressure chamber C8, the communication between the first master hydraulic pressure chamber C1 and the hydraulic pressure chamber C8 is blocked by the seal member S5, and the piston member AP2 does not operate and the master pistons MP1 and MP2 are not operated. In accordance with the forward movement, the brake fluid pressure is output from the first master fluid pressure chamber C1 and the second master fluid pressure chamber C2 to the fluid pressure systems H1 and H2. Further, when a hydraulic pressure is generated in the first master hydraulic chamber C1 due to the operation of the master piston MP1 (first piston) according to the brake operation by the driver, this hydraulic pressure is applied to the seal member S5. Even when the hydraulic pressure source PG or the like is normal, the driver can experience this if the sealing function of the sealing member S5 is impaired.

It is sectional drawing of the brake hydraulic pressure generator for vehicles which concerns on one Embodiment of this invention. It is a lineblock diagram showing an outline of a hydraulic brake device for vehicles provided with a brake fluid pressure generator for vehicles concerning one embodiment of the present invention. It is sectional drawing which shows the other example of the master piston with which it uses for the brake fluid pressure generator for vehicles which concerns on one Embodiment of this invention. It is sectional drawing of the brake hydraulic pressure generator for vehicles which concerns on other embodiment of this invention.

Explanation of symbols

HS Cylinder housing BP Brake pedal MP1, MP2 Master piston C1 First master hydraulic chamber C2 Second master hydraulic chamber C3, C4, C5 Atmospheric chamber C6, C8 Simulator hydraulic chamber C7, C9 Simulator atmospheric chamber P8, P11 Communication hole PG Fluid pressure source RS Atmospheric pressure reservoir E1, E2, E3, E4 Compression spring AB, AB2 Stroke simulator AP, AP2 Piston member NO1, NO2 Electromagnetic on-off valve SV1, SV3 First proportional solenoid valve SV2, SV4 Second Proportional solenoid valve

Claims (2)

  A first master liquid is slidably accommodated in the cylinder housing and moved back and forth in conjunction with the brake operation member, and slidably accommodated in the cylinder housing and the first piston. A pressure chamber is formed, and a second piston that forms a second master hydraulic pressure chamber with the cylinder housing, and an output hydraulic pressure of the first master hydraulic pressure chamber communicated with the first master hydraulic pressure chamber A stroke simulator that absorbs the amount of fluid corresponding to the first piston and applies a stroke according to the operating force of the brake operating member to the first piston, and the first master hydraulic chamber and the stroke simulator communicate with each other In the first master hydraulic chamber, and when the second piston is in the initial position, the first master hydraulic chamber and the stroke And a communication control means for blocking communication between the first master hydraulic chamber and the stroke simulator by the seal member when the second piston moves forward a predetermined distance or more from an initial position. In the vehicular brake hydraulic pressure generator, the seal member is disposed in the cylinder housing, and the communication control means further includes a communication hole formed in a direction intersecting with a central axis of the second piston, When the two pistons are in the initial position, the first master hydraulic pressure chamber communicates with the stroke simulator via the communication hole, and when the second piston moves forward a predetermined distance or more from the initial position, the seal The communication hole is separated from the first master hydraulic chamber by a member, and the first master hydraulic chamber and the stroke simulator are separated. Vehicle brake hydraulic pressure generating device, characterized by being configured so as to block the communication between the over data. The vehicular brake hydraulic pressure generator according to claim 1, wherein the stroke simulator is accommodated in the second piston.

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