JP6642293B2 - Brake equipment - Google Patents

Description

  The present invention relates to a brake device including a stroke simulator used for a vehicle brake device.

In an electronically controlled vehicle brake device, the brake device is driven not by the operating force of a brake operating member but by a driving force by electronic control. In a normal brake operation of the brake device, the brake fluid pushed out of the master cylinder by the operation force of the brake operation member is sent to a stroke simulator instead of the hydraulic brake of the wheels.
Patent Literature 1 describes an electronically controlled brake device including the above master cylinder and stroke simulator.

JP-A-2004-338852

  In the master cylinder of the brake device configured as described above, the input piston connected to the brake pedal moves forward by depressing the brake pedal. The input piston is urged rearward by a spring, and when the brake pedal is suddenly returned, the retraction speed of the input piston becomes excessive, so that a tapping sound is generated at the connection portion between the input piston and the brake pedal that has retreated. May occur.

  An object of the present invention is to provide a brake device capable of suppressing occurrence of a tapping sound by reducing a retreat speed of an input piston when a brake pedal is returned.

In order to solve the above problems, the present invention provides a brake device including a master cylinder and a stroke simulator, wherein the master cylinder moves forward when a brake operating member is depressed; An input chamber formed in front of a piston, wherein the brake fluid flows out to the stroke simulator when the input piston advances, and the brake fluid flows from the stroke simulator when the input piston retreats, The brake device is further provided in a connection passage connecting the input chamber and the stroke simulator, and further includes a restriction unit configured to restrict a flow of the brake fluid between the input chamber and the stroke simulator. Is the input chamber when the brake operating member is depressed. The restriction amount of the flow of the brake fluid flowing from the stroke simulator to the input chamber when the brake operating member is returned is larger than the restriction amount of the flow of the brake fluid flowing to the stroke simulator. The brake fluid that flows from the stroke simulator to the input chamber without blocking the flow of the brake fluid flowing from the input chamber to the stroke simulator. A first brake fluid passage including a check valve that shuts off the flow of the brake fluid, and a first orifice that restricts the flow of the brake fluid; and a connection passage that bypasses the check valve and the first orifice. A second brake fluid passage provided with a second orifice for restricting the flow of the brake fluid; Wherein the said the flow path area of the first orifice sum of the flow passage area of the second orifice, characterized in that equal to the flow area of the connecting passage when the restriction in the connecting passage is not provided Is realized.

With the configuration described above, when the brake operation member is depressed, the input piston advances, and the brake fluid flows from the input chamber through the restriction section to the stroke simulator. When the brake operating member is returned from the depressed position, the input piston retreats, and the brake fluid flows from the stroke simulator through the restriction to the input chamber.
Here, in the above configuration, the restriction amount of the flow of the brake fluid when returning the brake operation member is larger than the restriction amount of the flow of the brake fluid when the brake operation member is depressed, This means that the brake fluid is less likely to flow when the brake operating member is returned than when the brake operating member is depressed. Therefore, the return speed of the input piston when the brake operating member returns can be reduced.

Note that, as a configuration in which the brake fluid is less likely to flow when the brake operation member is returned than when the brake operation member is depressed, for example, the flow area of the restriction portion is smaller than when the brake operation member is depressed. Reducing the flow passage area of the restricting portion when returning the brake operating member may be mentioned.
By reducing the flow path area of the restricting portion when the brake operating member is returned, the flow rate of the brake fluid at the time of depressing the brake operating member is smaller than the flow amount of the brake fluid when returning the brake operating member. The restriction amount of the flow of the brake fluid increases. Therefore, the return speed of the input piston when returning the brake operation member can be reduced.

  Further, as another configuration in which the brake fluid is less likely to flow when returning the brake operation member than when depressing the brake operation member, without changing the flow area of the restricting portion, Only when returning, the flow of the brake fluid is interrupted for a certain period of time. Only when the brake operating member is returned, the flow path of the restricting portion is shut off for a certain period of time, so that when the brake operating member is returned, the flow rate of the brake fluid when the brake operating member is depressed is limited. The restriction amount of the flow of the brake fluid can be increased. Therefore, even when the flow path area of the restricting portion is the same when the brake operation member is stepped on and when the brake operation member is returned, the restriction amount of the flow of the brake fluid when the brake operation member is returned is reduced. And the return speed of the input piston can be reduced.

In the brake device, the sum of the flow area of the first orifice and the flow area of the second orifice is equal to the flow area of the connection passage when the restriction is not provided in the connection passage. Can be equal to

With the configuration described above, when the brake operation member is depressed, the flow area of the restricting portion is equal to the flow area of the first brake fluid passage and the flow passage area of the throttle of the second brake fluid passage. It is the sum of the flow channel areas. The flow passage area of the restriction portion when the brake operation member is returned is the flow passage area of the throttle because the first brake fluid passage is blocked by the check valve.
Therefore, the flow area of the brake fluid flowing through the restriction portion when the brake operation member is returned is larger than the flow area of the brake fluid flowing through the restriction portion when the brake operation member is depressed. Become smaller. Thereby, the return speed of the input piston when returning the brake operation member can be reduced.
Further, since the sum of the flow path area of the first orifice and the flow path area of the second orifice is equal to the flow path area of the connection passage when the restricting portion is not provided in the communication passage, the brake operation is performed. Only the speed at which the brake operation member returns can be reduced without increasing the reaction force acting when the member is depressed.
The second orifice may be a variable orifice capable of adjusting the flow area of the second orifice .

Further, in the brake device, the master cylinder further includes an output piston located in front of the input piston,
The output piston sends the brake fluid in an output chamber provided in front of the output piston to a hydraulic brake of a wheel by moving the brake fluid forward by hydraulic pressure from a pressurizing source. Composed,
The input chamber may be formed between the input piston and the output piston.

Since the input chamber communicates with the stroke simulator, the hydraulic pressure in the input chamber does not become high even if the input piston moves forward. On the other hand, the hydraulic pressure in the output chamber becomes high because the output chamber communicates with the hydraulic brake when the output piston advances. In order to withstand the high pressure in the output chamber, the member that seals the output piston is configured to increase the sliding resistance with the master cylinder. On the other hand, the sliding resistance of the member that seals the input piston with the master cylinder is not as high as the member that seals the output piston. Further, as described above, the input chamber is formed between the input piston and the output piston, and the input piston and the output piston are separated.
Therefore, in the brake device in which the input chamber is formed between the input piston and the output piston, compared to the brake device in which the input piston and the output piston are not separated, the brake operation member The return speed of the input piston at the time of return may increase. In such a brake device, the return speed of the input piston can be reduced by the restriction portion.

  By providing the restricting portion between the input chamber and the stroke simulator, the return speed of the input piston when returning the brake operating member can be reduced.

It is a figure showing the whole brake device composition of a 1st embodiment. FIG. 2 is a perspective view showing an assembly portion of the brake pedal and the clevis according to the first embodiment. It is a figure showing the composition of the diaphragm part of the 1st modification of a 1st embodiment.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.

<Structure of brake device>
FIG. 1 is a diagram showing an overall configuration of a brake device 2 according to a first embodiment of the present invention. The brake device 2 includes a hydraulic brake device 4, a brake pedal 6, an electronic control unit 8, and a hydraulic pressure generator 10.

<Hydraulic brake device>
The hydraulic brake device 4 includes a hydraulic brake 12 provided on wheels 11 and a slip control valve device 14 that can be individually controlled by electronic control.
Hydraulic brakes 12FL and 12FR are provided on the left and right front wheels 11FL and 11FR, and hydraulic brakes 12RL and 12RR are provided on the left and right rear wheels 11RL and 11RR. Each of the hydraulic brakes 12 includes a brake cylinder 16FL, 16FR, 16RL, 16RR to which brake fluid is supplied from the hydraulic pressure generator 10, and suppresses rotation of the wheels 11 by the hydraulic pressure of the supplied brake fluid. Hereinafter, when there is no need to distinguish the wheel position, FL, FR, RL, and RR may be omitted.
The slip control valve device 14 includes two electronic control valves provided between each of the hydraulic brakes 12 and the hydraulic pressure generating device 10, and individually controls the hydraulic pressure of each hydraulic brake 12. Since the slip control valve device 14 is a general one and has a small technical relationship with the present embodiment, a detailed description thereof will be omitted.

<Brake pedal>
FIG. 2 shows a mounting portion of the brake pedal 6 and the clevis 17. FIG. 1 shows the brake pedal 6, a master cylinder 30, which will be described later, and a connecting member between the brake pedal 6 and the master cylinder 30, and other members are omitted.
The brake pedal 6 is connected via a clevis 17 and an operating rod 18 to an input piston 42 of the master cylinder 30 which will be described later. As shown in FIG. 2, the clevis 17 is a U-shaped plate-shaped member, and a pair of clevis holes 20 facing each other are formed at each of the two distal ends. A connecting portion 22 connected to the brake pedal 6 is inserted between the two tip portions of the clevis 17. In this state, the clevis pin 24 is inserted so as to penetrate a not-shown connection hole formed in the connection portion 22 and the pair of clevis holes 20. The state where the clevis pin 24 has penetrated the pair of clevis holes 20 and the connection hole is maintained by the fastener 26, so that the brake pedal 6 and the clevis 17 are connected.
The brake pedal 6 is urged upward (in a direction in which the brake pedal 6 returns from a depressed state) by a pedal spring 28. The brake pedal 6 is provided with a stroke sensor 29 for detecting the position of the brake pedal 6.

<Electronic control unit>
In addition to the stroke sensor 29, a reaction force sensor 161, an accumulator pressure sensor 90, and a servo pressure sensor 136 described below are connected to the electronic control unit 8. Further, the communication control valve 158, the reservoir communication valve 160, the electromagnetic linear control valve device 80, the slip control valve device 14, and the pump motor 84 are connected to the electronic control unit 8.

<Hydraulic pressure generator>
As shown in FIG. 1, the hydraulic pressure generator 10 includes a master cylinder 30, a stroke simulator 32, a back hydraulic control unit 34, a throttle unit 36, and a reservoir 38.
[Master cylinder]
The master cylinder 30 includes a housing 40 which is a hollow cylindrical member, and an input piston 42 and a first output piston which are fitted to the inner peripheral portion of the housing 40 in series with each other so as to be liquid-tight and slidable. 44, a second output piston 46. The direction in which the input piston 42 moves when the brake pedal 6 is depressed is defined as forward, and the direction in which the input piston 42 moves when the brake pedal 6 is returned is defined as backward. An input chamber 48, a first output chamber 50, and a second output chamber 52 are formed in front of the input piston 42, the first output piston 44, and the second output piston 46, respectively.

The input piston 42 is formed in a bottomed cylindrical shape, and the operating rod 18 is fixed to a bottom surface inside the input piston 42. The rear end of the operating rod 18 is connected to the rear end of the spring 54 via a connecting member 55. The front end of the spring 54 is connected to the rear end of the housing 40. As a result, the input piston 42 is urged rearward by the spring 54. The input chamber 48 formed in front of the input piston 42 communicates with a simulator chamber 146 described below when a communication control valve 158 described below is opened.
The first output piston 44 and the second output piston 46 are provided with a first return spring 56 and a second return spring 58, respectively. The first output piston 44 and the second output piston 46 are urged rearward by the first return spring 56 and the second return spring 58.

The first output piston 44 includes a rear small-diameter portion 60 provided at a rear portion, an intermediate piston portion 62 provided at an intermediate portion, and a front piston portion 64 provided at a front portion. The rear small diameter portion 60 slides on the inner peripheral surface of the inner peripheral side protrusion 66 formed in a cylindrical shape on the inner peripheral surface of the housing 40. The intermediate piston portion 62 is located in front of the inner peripheral side protrusion 66 and slides on the inner peripheral surface of the housing 40. The front piston portion 64 is formed so that the diameter is smaller than that of the intermediate piston portion 62.
With the above structure, a rear chamber 68 is formed between the inner peripheral side projection 66 of the housing 40 and the intermediate piston section 62, and an annular chamber 70 is formed between the outer peripheral surface of the front piston section 64 and the inner peripheral surface of the housing 40. It is formed. The rear chamber 68 is connected to a rear hydraulic pressure control device 34 described later via a rear chamber connection passage 69.
The first output piston 44 is configured such that the pressure receiving area at the rear end of the rear small diameter portion 60 of the first output piston 44 to receive the hydraulic pressure is equal to the pressure receiving area at the front end of the intermediate piston portion 62. Formed. When the input chamber 48 and the annular chamber 70 communicate with each other, the force for moving the first output piston 44 forward and the force for moving the first output piston 44 backward are balanced.

  When the first output piston 44 and the second output piston 46 are advanced, the first output chamber 50 communicates with the hydraulic brakes 12RR, 12RL of the left and right rear wheels 11RR, 11RL via the liquid passage 72, and the second output The chamber 52 communicates with the hydraulic brakes 12FR, 12FL of the left and right front wheels 11FR, 11FL via a liquid passage 74. On the other hand, in a state where the first output piston 44 and the second output piston 46 are retracted until the rear end of the intermediate piston portion 62 contacts the inner peripheral side projection 66, the first output chamber 50 and the second output chamber 52 communicates with the reservoir 38.

<Back hydraulic control device>
The back hydraulic pressure control device 34 includes a high pressure source device 76, a regulator 78, and an electromagnetic linear control valve device 80.
[High pressure source device]
The high-pressure source device 76 detects a pump device 86 including a pump 82 and a pump motor 84, an accumulator 88 that stores the brake fluid sent from the pump device 86 in a high-pressure state, and a hydraulic pressure of the brake fluid stored in the accumulator 88. An accumulator pressure sensor 90 is included. The pump device 86 is controlled such that the accumulator pressure detected by the accumulator pressure sensor 90 is kept within the range of the set value. The high-pressure source device 76 corresponds to a pressure source.

[regulator]
The regulator 78 includes a housing 92, a pilot piston 94, a movable sleeve 96, and a spool valve mechanism 98. The pilot piston 94 and the movable sleeve 96 are fitted to the housing 92 in a liquid-tight and slidable manner so as to be in series with each other.
The pilot piston 94 is formed in a cylindrical shape with a bottom, and includes a buffer piston 100 on an inner peripheral portion. The open end of the pilot piston 94 and the buffer piston 100 abut on the movable sleeve 96.
The spool valve mechanism 98 includes a spool 102 and a spool holding cylinder 104 that slidably holds the spool 102. In FIG. 1, the direction in which the spool 102 moves when the brake pedal 6 is depressed is defined as forward, and the direction in which the spool 102 moves when the brake pedal 6 is returned is defined as backward. The spool holding cylinder 104 is fitted into and fixed to a front part of the housing 92.

A first pilot pressure chamber 106 is provided between the rear end of the pilot piston 94 and the housing 92, and a second pilot pressure chamber 108 is provided between the rear end of the spool 102 and the movable sleeve 96. A pressure adjusting chamber 110 is provided between the end and the housing 92.
The spool 102 is a cylindrical member having an open front end, and the pressure regulation chamber 110 also includes the inner periphery of the spool 102.
The housing 92 includes a high pressure source port 114 communicating with the high pressure source device 76, a servo pressure port 116 communicating with the rear chamber 68 of the master cylinder 30, a pressure increasing linear valve port 118 communicating with a pressure increasing linear valve 138 described later, A pressure reducing linear valve port 120 communicating with a pressure reducing linear valve 140 described later, a low pressure source port 122 communicating with the reservoir 38, an output chamber port 124 communicating with the first output chamber 50 of the master cylinder 30, and communicating with the brake cylinders 16RR and 16RL. A brake device port 126 is formed.

The rear end of the spool 102 is exposed from the rear end of the spool holding tube 104 and contacts the movable sleeve 96. The portion where the spool 102 and the movable sleeve 96 abut is the rearward moving end of the spool 102. The spool 102 is urged rearward by the separation spring 128.
A low pressure source passage 130, a high pressure source passage 132, and a servo pressure passage 134 are formed in the spool holding cylinder 104. The low pressure source passage 130 is connected to the low pressure source port 122 via the internal passage, the high pressure source passage 132 is connected to the high pressure source port 114 via the internal passage, and the servo pressure passage 134 is connected to the servo pressure port 116 via the internal passage. Connected to.

When the spool 102 is located at the rear moving end, the servo pressure passage 134 communicates with the pressure regulation chamber 110, the low pressure source passage 130 formed in the housing 92, and the low pressure source port 122. The high-pressure source passage 132 is closed by the outer peripheral surface of the spool 102, and the connection with the pressure regulation chamber 110 is cut off. That is, when the spool 102 is located at the rear end, the rear chamber 68 communicates with the reservoir 38.
When the spool 102 moves forward, a gap is formed between a concave portion formed on the outer peripheral surface of the spool 102 and the inner peripheral surface of the spool holding cylinder 104, so that the servo pressure passage 134, the high pressure source passage 132, the pressure regulation chamber The communication between the pressure regulating chamber 110 and the low pressure source passage 130 is interrupted. That is, the rear chamber 68 and the high-pressure source device 76 are communicated via the pressure regulation chamber 110, and the brake fluid is supplied to the rear chamber 68. Between the servo pressure port 116 and the rear chamber 68, a servo pressure sensor 136 for detecting the liquid pressure in the rear chamber 68 is provided.

[Electromagnetic linear control valve device]
The electromagnetic linear control valve device 80 includes a pressure increasing linear valve 138 and a pressure reducing linear valve 140. The pressure increasing linear valve 138 is provided between the high pressure source device 76 and the pressure increasing linear valve port 118 of the regulator 78. The pressure reducing linear valve 140 is provided between the pressure reducing linear valve port 120 of the regulator 78 and the reservoir 38. When no current is supplied to the solenoid of the control valve, the pressure increasing linear valve 138 is a normally closed valve that is closed, and the pressure reducing linear valve 140 is a normally open valve that is open.

When the brake pedal 6 is depressed, the pressure-increasing linear valve 138 opens and the pressure-reducing linear valve 140 closes, so that the brake fluid is supplied to the second pilot pressure chamber 108 and is located at the rear end. The spool 102 moves forward. In this state, the communication between the pressure regulating chamber 110 and the reservoir 38 is interrupted, and the pressure regulating chamber 110 communicates with the rear chamber 68 and the high-pressure source device 76. Flows into.
At this time, since the hydraulic pressure in the pressure adjustment chamber 110 increases, the spool 102 is urged rearward by the hydraulic pressure in the pressure adjustment chamber 110. That is, a force that is advanced by the hydraulic pressure of the second pilot pressure chamber 108 and a force that is retracted by the hydraulic pressure of the pressure adjustment chamber 110 act on the spool 102. Further, the pressure receiving area of the spool 102 for receiving the hydraulic pressure in the second pilot pressure chamber 108 is substantially equal to the pressure receiving area of the spool 102 for receiving the hydraulic pressure. Therefore, the spool 102 is maintained at a position where the hydraulic pressure in the second pilot pressure chamber 108 and the hydraulic pressure in the pressure adjustment chamber 110 are balanced. As a result, the hydraulic pressure in the second pilot pressure chamber 108 and the hydraulic pressure in the rear chamber 68 are adjusted to substantially the same magnitude.
Note that the biasing force of the separation spring 128 on the spool 102 is relatively small and is ignored.

  Further, the first output piston 44 advances due to the increase in the hydraulic pressure of the rear chamber 68, and the brake fluid flows out of the first output chamber 50. The brake fluid flowing out of the first output chamber 50 flows into the hydraulic brakes 12RR and RL via the output chamber port 124 of the regulator 78, the first pilot pressure chamber 106, and the brake device port 126. As a result, the hydraulic brakes 12RR and RL operate.

  When the depressed brake pedal 6 is released, the pressure-reducing linear valve 140 described later opens and the pressure-increasing linear valve 138 closes, whereby the hydraulic pressure in the second pilot pressure chamber 108 decreases, and the spool 102 fall back. In this state, the rear chamber 68 communicates with the reservoir 38 via the pressure adjustment chamber 110, and the communication with the high-pressure source device 76 is cut off. As the hydraulic pressure in the rear chamber 68 decreases, the first output piston 44 retreats, and the brake fluid is drawn back from the brake cylinders 16RR, 16RL to the first output chamber 50. As a result, the braking force of the hydraulic brakes 12RR and RL decreases.

<Stroke simulator>
The stroke simulator 32 includes a housing 142 and a simulator piston 144 that is slidably fitted to the housing 142 in a liquid-tight manner. A simulator chamber 146 is formed between the housing 142 and the simulator piston 144. In FIG. 1, the direction in which the simulator piston 144 moves when the brake fluid flows from the master cylinder 30 into the simulator chamber 146 is downward, and the direction in which the simulator piston 144 moves when the brake fluid flows out from the simulator chamber 146 to the master cylinder 30. Upward. The simulator piston 144 is urged upward by a spring 148 connected to the lower end of the simulator piston 144 and the housing 142.

The simulator chamber 146 of the stroke simulator 32 is connected to the input chamber 48, the annular chamber 70, and the reservoir 38 of the master cylinder 30 via the connection passage 150. The connection passage 150 includes an annular chamber connection passage 152, a reservoir connection passage 154, and a simulator room connection passage 156.
The annular chamber connection passage 152 connects the input chamber 48 and the annular chamber 70. A communication control valve 158 which is an electromagnetic on-off valve is provided in the annular chamber connection passage 152. The communication control valve 158 is a normally-closed valve whose opening and closing are controlled by ON / OFF of a supplied current, and is closed in an OFF state where no current is supplied. The reservoir connection passage 154 connects the input chamber 48, the annular chamber 70, and the reservoir 38. A reservoir communication valve 160 is provided between the input chamber 48 and the annular chamber 70 and the reservoir 38. The reservoir communication valve 160 is a normally-open electromagnetic on-off valve.
When the brake pedal 6 is depressed, a brake switch (not shown) provided on the brake pedal 6 detects depression of the brake pedal 6, the communication control valve 158 is opened, and the reservoir communication valve 160 is closed. Become. Similarly, when the brake pedal is returned to the initial position, the brake switch detects the return of the brake pedal 6, the communication control valve 158 is closed, and the reservoir communication valve 160 is opened. When the communication control valve 158 is closed and the reservoir communication valve 160 is opened, the brake fluid in the simulator chamber 146 flows out to the reservoir 38.

The simulator room connection passage 156 connects the input room 48, the annular room 70, and the simulator room 146 of the stroke simulator 32. Simulator room connection passage 156 joins annular room connection passage 152 and reservoir connection passage 154 and shares a part of the passage. A reaction force sensor 161 and a throttle unit 36 are provided in the simulator room connection passage 156. The flow direction of the brake fluid when the brake pedal 6 is depressed and the brake fluid flows from the input chamber 48 to the simulator chamber 146 is defined as the flow direction at the time of depression. In the flow direction at the time of stepping, the input chamber 48 side is “upstream side” and the stroke simulator 32 side is “downstream side”. The throttle portion 36 is disposed downstream of the first junction portion 162, which is a portion where the simulator chamber connection passage 156 and the reservoir connection passage 154 join, in the flow direction when stepping on.
Further, a second junction 164, which is a portion where the simulator chamber connection passage 156 and the annular chamber connection passage 152 join, is located upstream of the first junction 162 in the flow direction when stepping on. A communication control valve 158 is provided between the second junction 164 of the simulator chamber connection passage 156 and the input chamber 48.

<Aperture section>
The throttle unit 36 is provided in the simulator chamber connection passage 156 and includes a main passage 166 and a sub passage 168 formed so as to bypass the main passage 166.
The main passage 166 includes a first orifice 170 and a check valve 172. The first orifice 170 is located upstream of the check valve 172 in the flow direction when stepping on, and throttles the flow of the brake fluid passing through the first orifice 170 regardless of the flow direction. The flow passage area of the first orifice 170 is S _1.
The check valve 172 does not block the flow of the brake fluid flowing from the input chamber 48 of the master cylinder 30 to the simulator chamber 146 of the stroke simulator 32, but blocks the flow of the brake fluid flowing from the simulator chamber 146 to the input chamber 48.
The sub passage 168 is formed so as to bypass the first orifice 170 and the check valve 172 of the main passage 166. The secondary passage 168 is provided with a second orifice 174. The second orifice 174 restricts the flow of the brake fluid passing through the second orifice 174 regardless of the flowing direction. The flow passage area of the second orifice 174 is S _2.

<Operation when the brake pedal is depressed>
When the brake pedal 6 is depressed, a current is supplied from the electronic control unit 8, the communication control valve 158 opens, and the reservoir communication valve 160 closes. Thus, the input chamber 48 and the annular chamber 70 of the master cylinder 30 and the simulator chamber 146 of the stroke simulator 32 communicate with each other. At the same time, the input piston 42 of the master cylinder 30 moves forward with the movement of the brake pedal 6. In addition, the first output piston 44 moves forward by the pressurized brake fluid flowing into the rear chamber 68 when the rear hydraulic pressure control device 34 operates. As the input piston 42 and the first output piston 44 advance, the brake fluid flows from the input chamber 48 and the annular chamber 70 to the simulator chamber 146.

The brake fluid flowing out of the input chamber 48 and the annular chamber 70 passes through the first orifice 170 and the check valve 172 provided in the main passage 166 of the simulator chamber connection passage 156, and the second orifice 174 provided in the sub-passage 168. And flows into the simulator room 146.
Therefore, the flow passage area of the throttle portion 36 when the brake pedal 6 is depressed is the sum (S ₁ + S ₂ ) of the flow passage area of the first orifice 170 and the flow passage area of the second orifice 174.

  When the brake fluid flows into the simulator chamber 146, the simulator piston 144 located at the upper end moves downward due to the hydraulic pressure of the brake fluid that has flowed. Further, the second output piston 46 advances due to the advance of the first output piston 44, and the hydraulic brake device 4 is operated by the pressurized hydraulic pressure of the first output chamber 50 and the second output chamber 52.

<Operation when the depressed brake pedal is released>
When the brake pedal 6 is returned from the depressed position, the communication control valve 158 opens and the reservoir communication valve 160 remains closed. The input piston 42 is retracted by the urging of the spring 54 and the pedal spring 28 which urges the brake pedal 6 in a direction to return from the depressed position. Further, the first output piston 44 is retracted by the brake fluid in the rear chamber 68 flowing through the pressure regulating chamber 110 of the regulator 78 and the low-pressure source passage 130 to the reservoir 38. As the input piston 42 and the first output piston 44 retract, brake fluid flows from the simulator chamber 146 to the input chamber 48 and the annular chamber 70.

When the brake fluid flows from the simulator chamber 146 to the input chamber 48 and the annular chamber 70, the flow of the brake fluid passing through the main passage 166 of the simulator chamber connection passage 156 is blocked by the check valve 172. Therefore, the brake fluid flowing out of the simulator chamber 146 does not pass through the first orifice 170 of the main passage 166, passes through only the second orifice 174 of the sub passage 168, and flows into the input chamber 48.
Therefore, the flow passage area of the throttle portion 36 when the brake pedal 6 is returned is the flow passage area (S ₂ ) of the second orifice 174.

  When the first output piston 44 moves backward, the second output piston 46 also moves backward. Thereby, the brake fluid of the hydraulic brake device 4 is returned to the first output chamber 50 and the second output chamber 52, and the braking force of the hydraulic brake device 4 is reduced.

Therefore, in the first embodiment, the flow path area (S ₂ ) of the throttle section 36 when the brake pedal 6 is returned is set to the flow path area (S ₁ + S) of the throttle section 36 when the brake pedal 6 is depressed. ₂ ) can be smaller than. As a result, the flow rate of the brake fluid when returning the brake pedal 6 is larger than the flow rate of the brake fluid when the brake pedal 6 is depressed, so that the return speed of the input piston 42 can be reduced. it can.
Note that by reducing the flow path area of the second orifice 174, the return speed of the input piston 42 can be made sufficiently small. On the other hand, when the brake pedal 6 is depressed, The acting reaction force may increase. Therefore, in order to reduce the excessive reaction force acting when the brake pedal 6 is depressed while maintaining the return speed of the input piston 42 when the brake pedal is returned, the flow path of the first orifice 170 must be reduced. It is conceivable that the area is set to be larger than the flow path area of the second orifice 174.

The sum (S ₁ + S ₂ ) of the flow path area when the brake pedal 6 is depressed in the main passage 166 and the sub passage 168 when the throttle portion 36 is provided is the simulator when the throttle portion 36 is not provided. Consider a case in which the chamber connection passage 156 is configured to be equal to the flow passage area when the brake pedal 6 is depressed. In this case, the reaction force exerted when the brake pedal 6 is depressed has the same value.
On the other hand, when the brake pedal 6 is returned, the flow path area of the flowing brake fluid can be reduced by providing the throttle portion 36 as compared with the case where the throttle portion 36 is not provided. Under this condition, the return speed of the input piston 42 depends on the flow area of the brake fluid flowing when the brake pedal 6 is released. Therefore, the return speed of the input piston 42 is lower when the throttle unit 36 is provided than when the throttle unit 36 is not provided.
Therefore, only the speed at which the brake pedal 6 returns can be reduced without increasing the reaction force acting when the brake pedal 6 is depressed. Thus, it is possible to reduce the tapping sound generated when the brake pedal 6 returns suddenly when the brake pedal 6 is returned.

In the brake device 2 of the present embodiment, the input chamber 48 communicates with the simulator chamber 146, so that the input piston 42 does not become high pressure even if the input piston 42 moves forward. When the one-output piston 44 advances, the pressure becomes high because it communicates with the brake cylinders 16RR and RL. In order to withstand the high pressure in the first output chamber 50, the member that seals the first output piston 44 is configured to increase the sliding resistance with the master cylinder 30. On the other hand, the sliding resistance of the member sealing the input piston 42 with the master cylinder 30 is not as high as the member sealing the first output piston 44. An input chamber 48 is formed between the input piston 42 and the first output piston 44, and the input piston 42 and the first output piston 44 are separated.
Therefore, the return speed of the input piston 42 when the brake pedal 6 returns is greater than that of a brake device in which the input piston 42 and the first output piston 44 are not separated. The return speed of the input piston 42 can be adjusted by the throttle section 36.
<First Modification>

  The structure of the aperture portion is not limited to the structure of the above embodiment, and may be as shown in FIG. The brake device of the present modified example has the same configuration as the brake device 2 of the first embodiment, and is different only in the throttle unit 176. Therefore, the configuration and operation of the throttle unit 176 will be mainly described.

FIG. 3 shows the configuration of the diaphragm unit 176 of the present modification. The throttle portion 176 includes a main passage 166 and a sub passage 168 formed so as to bypass the main passage 166. The main passage 166 includes a first orifice 170 and a check valve 172. The first orifice 170 is located upstream of the check valve 172 in the flow direction when stepping on.
The sub passage 168 is formed so as to bypass the first orifice 170 and the check valve 172 of the main passage 166, and includes a variable orifice 178. The variable orifice 178 is an orifice whose throttle area can be adjusted regardless of the direction in which the flow of the brake fluid passing through the variable orifice 178 flows. The throttle unit 176 is provided with an adjusting mechanism for adjusting the flow area of the variable orifice 178, and the adjustment of the flow area of the variable orifice 178 is manually performed by an operator.

  The flow of the brake fluid in the simulator room connection passage 156 when the brake pedal 6 is depressed will be described. The brake fluid flowing out of the input chamber 48 and the annular chamber 70 flows into the simulator chamber 146 through the first orifice 170, the check valve 172, and the variable orifice 178. The flow passage area of the throttle 176 is the sum of the flow passage area of the first orifice 170 and the flow passage area of the variable orifice 178.

  The flow of the brake fluid in the simulator room connection passage 156 when the depressed brake pedal 6 is returned will be described. Brake fluid flows from the simulator chamber 146 to the input chamber 48 and the annular chamber 70. The brake fluid flowing out of the simulator chamber 146 does not pass through the main passage 166 blocked by the check valve 172, passes through only the variable orifice 178, and flows into the input chamber 48. Therefore, when the brake pedal 6 is returned, the flow path area of the throttle section 176 becomes the flow path area of the variable orifice 178, and the flow path area of the throttle section 176 when the brake pedal 6 is returned from when the brake pedal 6 is depressed. The area becomes smaller.

Therefore, by making the flow passage area of the variable orifice 178 smaller than the flow passage area of the first orifice 170, it is possible to return the brake pedal 6 without increasing the reaction force acting on the brake pedal 6 when the brake pedal 6 is depressed. The return speed of the input piston 42 at the time can be reduced. This makes it possible to reduce the tapping sound generated by the sudden return of the brake pedal 6.
Since the flow passage area of the variable orifice 178 can be adjusted even after the brake device 2 is mounted on the vehicle, the input piston can be adjusted according to the size of the mounted vehicle and the tendency of the operator of the brake pedal 6 when operating. The return speed of 42 and the strength of the reaction force to the brake pedal 6 can be manually adjusted.
<Second modification>

In the first embodiment, the throttle portion 36 is provided in the simulator chamber connection passage 156, and the flow path of the throttle portion 36 when the brake pedal 6 is returned is larger than the flow passage area of the throttle portion 36 when the brake pedal 6 is depressed. The return speed of the input piston 42 is reduced by reducing the area. On the other hand, in the second modification of the first embodiment, the return speed of the input piston 42 when the brake pedal 6 is returned is reduced without providing the throttle portion 36.
When the brake pedal 6 is depressed, the communication control valve 158 is open as in the first embodiment, but when the brake pedal 6 is released, the communication control valve 158 that is open is closed for a certain period of time. Give a valve. (The communication control valve 158 may be closed for a certain period of time when the brake pedal 6 is returned, or the communication control valve 158 may be closed a plurality of times so that the total time of a plurality of times becomes a certain time. That is, the opening time of the communication control valve 158 of the second modified example when returning the brake pedal 6 is set shorter than the opening time of the communication control valve 158 of the first embodiment.
As a result, the restriction amount of the flow of the brake fluid when returning the brake pedal 6 is larger than the restriction amount of the flow of the brake fluid when the brake pedal 6 is depressed, so that the reaction force against the brake pedal 6 is not increased. Thus, the return speed of the input piston 42 can be reduced.

  2: Brake device 4: Hydraulic brake device 6: Brake pedal 8: Electronic control unit 10: Hydraulic pressure generating device 11: Wheel 12: Hydraulic brake 14: Slip control valve device 16: Brake cylinder 17: Clevis 18: Operating rod 20: Clevis hole 22: Connection part 24: Clevis pin 26: Fastener 28: Pedal spring 29: Stroke sensor 30: Master cylinder 32: Stroke simulator 34: Back pressure control device 36: Restrictor 38: Reservoir 40: Housing 42: Input piston 44: First output piston 46: Second output piston 48: Input chamber 50: First output chamber 52: Second output chamber 54: Spring 55: Connecting member 56: First return spring 58: Second return spring 60 :rear Diameter part 62: Intermediate piston part 64: Front piston part 66: Inner peripheral side projection part 68: Back chamber 70: Annular chamber 72: Liquid passage 74: Liquid passage 76: High pressure source device 78: Regulator 80: Electromagnetic linear control valve Device 82: Pump 84: Pump motor 86: Pump device 88: Accumulator 90: Accumulator pressure sensor 92: Housing 94: Pilot piston 96: Movable sleeve 98: Spool valve mechanism 100: Buffer piston 102: Spool 104: Spool holding cylinder 106: First pilot pressure chamber 108: Second pilot pressure chamber 110: Pressure regulation chamber 114: High pressure source port 116: Servo pressure port 118: Pressure increasing linear valve port 120: Pressure reducing linear valve port 122: Low pressure source port 124: Output chamber port 126: Brake device port 128: separation spring 130: low pressure source passage 132: high pressure source passage 134: servo pressure passage 136: servo pressure sensor 138: pressure increasing linear valve 140: pressure reducing linear valve 142: housing 144: simulator piston 146: simulator room 148: spring 150 : Connection passage 152: Annular chamber connection passage 154: Reservoir connection passage 156: Simulator room connection passage 158: Communication control valve 160: Reservoir communication valve 161: Reaction force sensor 162: First junction 164: Second junction 166: Main Passage 168: Sub passage 170: First orifice 172: Check valve 174: Second orifice 176: Restrictor 178: Variable orifice

Claims (4)

A brake device including a master cylinder and a stroke simulator,
The master cylinder is
An input piston that moves forward when the brake operating member is depressed,
An input chamber formed in front of the input piston, wherein the brake fluid flows out to the stroke simulator when the input piston advances, and the brake fluid flows in from the stroke simulator when the input piston retreats. Prepared,
The brake device is:
A restriction unit provided in a connection passage connecting between the input chamber and the stroke simulator, the restriction unit restricting a flow of the brake fluid between the input chamber and the stroke simulator is further provided.
The limiting portion is more than the limited amount of the flow of the brake fluid flowing from the input chamber to the stroke simulator when the brake operating member is depressed, the stroke simulator when the brake operating member is returned from the stroke simulator. The limit amount of the flow of the brake fluid flowing to the input chamber is configured to be larger ,
The restriction unit is:
A check valve that is a passage provided in the connection passage and that does not block the flow of the brake fluid flowing from the input chamber to the stroke simulator, but blocks the flow of the brake fluid flowing from the stroke simulator to the input chamber. A first brake fluid passage including a first orifice for restricting a flow of the brake fluid;
A second brake fluid passage provided in the connection passage so as to bypass the check valve and the first orifice, the second brake fluid passage including a second orifice for restricting a flow of the brake fluid;
A brake , wherein the sum of the flow passage area of the first orifice and the flow passage area of the second orifice is equal to the flow passage area of the connection passage when the restriction is not provided in the connection passage. apparatus. The brake device according to claim 1 , wherein a flow passage area of the first orifice is larger than a flow passage area of the second orifice . The brake device according to claim 1, wherein a variable orifice having an adjustable flow passage area is provided as the second orifice in the second brake fluid passage. 4. The master cylinder further includes an output piston located in front of the input piston,
The output piston sends the brake fluid in an output chamber provided in front of the output piston to a hydraulic brake of a wheel by moving the brake fluid forward by hydraulic pressure from a pressurizing source. Composed,
The brake device according to any one of claims 1 to 3, wherein the input chamber is formed between the input piston and the output piston.

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