JPH07197961A - Hydraulic brake device - Google Patents

Abstract

PURPOSE:To reduce unconfortable feeling of a driver caused by dropping of a brake pedal when the brake pedal is operated and a car is stopped, in a hydraulic brake device provided with a servo hydraulic pressure generation chamber in which servo hydrauic pressure is generated based on co-rotation of a caliper at the braking time. CONSTITUTION:An opening/closing valve 152 is arranged on the way of a bypass passage 170 which communicates a caliper hydraulic pressure chamber with a servo hydraulic pressure generation chamber. A piston 158 is moved against energizing force of a spring 252 to interrupt the bypass passage 170. When a brake pedal is operated with a constant force, a hydraulic control valve is kept in a holding condition, so that brake liquid is prevented from being supplied to the servo hydraulic generation chamber through the hydraulic control valve. Dropping of the brake pedal is prevented even when the brake pedal is operated and a car is stopped to cause the hydraulic pressure in the servo hydraulic pressure generation chamber is atmospheric pressure or lower. A driver therefore does not feel unconformably.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic brake device, and more particularly to a servo hydraulic pressure generated by utilizing the accompanying torque applied from a disc rotor to a brake pad during braking. The present invention relates to a hydraulic brake device of the type that increases the hydraulic pressure of the brake cylinder to increase the braking force of the disc brake.

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication (Kokai) No. 57-30647 discloses
(a) A brake operation-compatible hydraulic pressure generator that generates hydraulic pressure in response to the operation of the brake operation member, and (b) a pad support member that supports the brake pad and a brake that presses the brake pad against the disc rotor by supplying hydraulic pressure. A brake actuator equipped with a cylinder and attached to a fixed member near the disk rotor so as to be rotatable in the rotation direction of the disk rotor; and (c) servo fluid that generates servo hydraulic pressure based on the accompanying rotation of the pad support member. A pressure generator,
(d) a first hydraulic chamber connected to the brake operation-compatible hydraulic pressure generating device, and a second hydraulic chamber connected to the brake operating device,
A third hydraulic chamber connected to the servo hydraulic pressure generator,
Communication between the first hydraulic chamber, the second hydraulic chamber and the third hydraulic chamber
A hydraulic brake device including a hydraulic control valve that controls the hydraulic pressure of the second hydraulic chamber to be higher than the hydraulic pressure of the first hydraulic chamber and to a height according to the hydraulic pressure of the first hydraulic chamber by shutting off. Is listed.

According to this hydraulic brake device, when the brake pad is pressed against the disk rotor, a rotating torque is generated in the pad supporting member, and the servo hydraulic pressure is generated in the servo hydraulic pressure generating device based on the torque.
When the accompanying torque becomes large to some extent, the servo hydraulic pressure becomes higher than the hydraulic pressure of the brake operation-compatible hydraulic pressure generator. Therefore, the hydraulic pressure control valve controls the communication / interruption between the brake operation-compatible hydraulic pressure generating device, the brake operating device, and the servo hydraulic pressure generating device, so that the hydraulic pressure of the brake operating device is changed to the brake operating compatible liquid. When the hydraulic pressure is equal to or higher than the hydraulic pressure of the pressure generating device, the magnitude is controlled according to the hydraulic pressure of the hydraulic pressure generating device corresponding to the brake operation.

When the vehicle stops with the brake operating member being operated, the accompanying torque applied from the disk rotor to the pad support member decreases, or the opposite accompanying torque acts in the opposite direction, and the liquid of the servo hydraulic pressure generator is applied. The pressure drops, and in some cases drops below atmospheric pressure. Rolling back occurs when the vehicle is braked and stopped. While the movement of the wheels is suppressed during deceleration, the vehicle body tries to continue to move forward due to the inertial force, so that elastic members such as suspensions provided between the vehicle body and the wheels are elastically deformed. Then, when the vehicle stops and the inertial force of the vehicle body disappears, the vehicle body is pulled back by the elastic force,
A swinging back occurs. As a result, a rotational torque in the direction opposite to that before the stop is generated on the wheels, and a counter rotating torque in the opposite direction acts. In addition, when the vehicle stops on an uphill road surface, a reverse accompanying torque is generated.

When the hydraulic pressure of the servo hydraulic pressure generator decreases or becomes lower than the atmospheric pressure, the hydraulic pressure of the brake actuator becomes higher and the hydraulic fluid flows out to the servo hydraulic pressure generator.
On the other hand, since the brake operating member is kept in the operating state, the hydraulic pressure of the brake operation-corresponding hydraulic pressure generating device (first hydraulic chamber) is maintained high. Therefore, the hydraulic pressure in the brake actuator (second hydraulic chamber) becomes lower than the hydraulic pressure in the brake operation-compatible hydraulic pressure generator (first hydraulic chamber), and the brake fluid flows out from the brake-operation-compatible hydraulic pressure generator. As a result, the operating stroke of the brake operating member increases sharply, which causes the driver to feel uncomfortable.

In order to prevent this, the hydraulic control valve has an original function of controlling the hydraulic pressure of the second hydraulic chamber to a height corresponding to the hydraulic pressure of the first hydraulic chamber (second hydraulic pressure). In addition to the chamber hydraulic pressure control function), a function of suppressing a sudden increase in the operation stroke of the brake operation member (abbreviated as a stroke sudden increase suppression function) is also performed. Between the second hydraulic chamber and the third hydraulic chamber, an opening / closing valve for suppressing a sudden increase in stroke is provided in series with the opening / closing valve for controlling the hydraulic pressure of the second hydraulic chamber. When the pressure drops, the on-off valve is closed to prevent the brake fluid from flowing out from the brake actuator to the servo hydraulic pressure generator.

[0007]

However, in this on-off valve, the hydraulic pressure in the servo hydraulic pressure generating device and the third hydraulic pressure chamber decreases, and a certain amount of brake fluid flows out from the brake operating device to cause the second hydraulic pressure. Since the hydraulic pressure in the chamber is lowered and becomes lower than the hydraulic pressure generator for the brake operation and lower than the hydraulic pressure in the first hydraulic chamber, it is completely closed so that a sudden increase in the operation stroke of the brake operating member is completely prevented. I couldn't do that, and I couldn't avoid making the driver feel uncomfortable. The first to third inventions of the present application have been made for the purpose of further reducing or completely preventing the sudden increase in the slot talk of the brake operating member, or facilitating the solution of the problem of the rapid stroke increase.

[0008]

The gist of the first invention is to provide the above-mentioned (a) brake operation-compatible hydraulic pressure generator, (b) brake actuator, (c) servo hydraulic pressure generator, (d) liquid. A hydraulic brake device equipped with a pressure control valve, which does not allow the flow of brake fluid from the latter to the former when the hydraulic pressure of the servo hydraulic pressure generator is lower than the hydraulic pressure of the brake actuator. And a bypass passage that connects the brake actuator and the servo hydraulic pressure generator by bypassing the hydraulic pressure control valve is provided, and the brake operation compatible hydraulic pressure generator and the brake actuator are provided in the middle of the bypass passage. There is an on-off valve that is opened when one of the hydraulic pressures is lower than the set value and closed when the hydraulic pressure is higher than the set value.

Here, the pad support member of the brake actuating device is a member that receives the accompanying torque during braking,
When the caliper is of the opposed type in which brake cylinders are provided on both sides of the disc rotor, the caliper serves as a pad support member because the brake pad is normally supported by the caliper. When the caliper has a brake cylinder only on one side of the disc rotor and is a floating type that can move in the axial direction of the disc rotor, the brake pad is usually supported by the mounting bracket that supports the caliper. The mounting bracket serves as a pad support member.

The gist of the second invention is that, in addition to the constituent elements of the first invention, a third part of the servo hydraulic pressure generator is provided in the middle of the liquid passage connecting the servo hydraulic pressure generator and the third hydraulic chamber. A check valve is provided to allow the flow of the hydraulic fluid to the hydraulic chamber, but prevent the flow in the reverse direction.

A third aspect of the present invention is to provide a hydraulic fluid equipped with (a) a brake operation-compatible hydraulic pressure generator, (b) a brake actuator, (c) a servo hydraulic pressure generator, and (d) a hydraulic pressure control valve. In the pressure brake device, the flow of hydraulic fluid from the reservoir to the servo hydraulic pressure generation device is allowed in the middle of the fluid passage connecting the reservoir and the servo hydraulic pressure generation device and the reservoir, but the reverse flow is blocked. That is, a stop valve was provided.

[0012]

In the hydraulic brake device according to the first aspect of the invention, the on-off valve is in the closed state before the vehicle stops with the brake operating member being operated. Since the on-off valve is installed in the bypass passage that connects the brake actuator and the servo hydraulic pressure generator by bypassing the hydraulic pressure control valve, the hydraulic pressure control valve's hydraulic pressure control of the brake actuator does not It is performed regardless of whether it is open or closed.
Therefore, close the on-off valve before the vehicle stops,
It is possible to block the bypass passage.

If the vehicle is stopped while the brake operating member is being operated, the accompanying torque of the pad supporting member will be reduced or the reverse direction will occur as described above, so that the servo hydraulic pressure is generated. The hydraulic pressure of the device drops,
In some cases, the atmospheric pressure is lower than atmospheric pressure, but at that time, the bypass passage connecting the brake actuator and the servo hydraulic pressure generator is cut off, and the hydraulic fluid of the brake actuator is blocked in the bypass passage. It is possible to prevent the fluid from flowing out to the servo hydraulic pressure generator.

On the other hand, in the hydraulic pressure control valve, if the operating force of the brake operating member is constant, the hydraulic pressure of the brake operating device is maintained and the brake operating device and the servo hydraulic pressure generating device are not communicated with each other. Absent. Therefore, the hydraulic fluid of the brake actuator is also prevented from flowing out to the servo hydraulic pressure generator via the hydraulic pressure control valve.

When the hydraulic pressure of the servo hydraulic pressure generating device is reduced by reducing the operating force of the brake operating member, the hydraulic fluid of the brake operating device or the hydraulic pressure control valve flows in. Since the hydraulic fluid of the brake operating force-corresponding hydraulic pressure generating device is supplied to the servo hydraulic pressure generating device through the bypass passage and the opening / closing valve, it is possible to favorably avoid the hydraulic fluid shortage in the servo hydraulic pressure generating device.

In the hydraulic brake device of the second invention,
When the hydraulic pressure of the servo hydraulic pressure generator becomes lower than the hydraulic pressure of the third hydraulic pressure chamber of the hydraulic pressure control valve, the hydraulic fluid may flow from the third hydraulic pressure chamber to the servo hydraulic pressure generator. Blocked by. For example, even if the hydraulic control valve brings the second hydraulic chamber and the third hydraulic chamber into communication by increasing the operating force of the brake operating member while the vehicle is stopped, the hydraulic fluid generates servo hydraulic pressure. It is prevented from being supplied to the device.

On the other hand, when the servo hydraulic pressure is generated in the servo hydraulic pressure generating device, the hydraulic fluid of the servo hydraulic pressure generating device is supplied to the third hydraulic pressure chamber through the check valve, and the hydraulic fluid in the third hydraulic pressure chamber is supplied. Since the hydraulic pressure is increased, if the third hydraulic chamber and the second hydraulic chamber are communicated with each other in the hydraulic control valve, the hydraulic pressure of the second hydraulic chamber is increased and the hydraulic pressure of the brake actuator is increased. The pressure is increased.

In the hydraulic brake device of the third invention,
If the hydraulic pressure of the servo hydraulic pressure generator becomes lower than the hydraulic pressure of the reservoir (often atmospheric pressure, but not essential),
The hydraulic fluid in the reservoir is supplied to the servo hydraulic pressure generator via the check valve. That is, according to the third aspect of the present invention, the brake fluid can be supplied to the servo hydraulic pressure generator from a route different from the brake actuator and the brake operation-compatible hydraulic pressure generator. It is not essential to supply the brake fluid from the corresponding hydraulic pressure generator, and it becomes easy to solve the problem of sudden increase in stroke of the brake operating member.

[0019]

As described above, according to the first invention, when the vehicle is stopped while the brake operating member is operated,
It is possible to prevent hydraulic fluid from flowing from the brake actuator to the servo hydraulic pressure generator via the bypass passage. Further, if the operating force of the brake operating member is constant, the hydraulic fluid of the brake operating device will not flow out to the servo hydraulic pressure generating device via the hydraulic pressure control valve. Therefore, if the operating force of the brake operating member is kept constant while the vehicle is stopped, the stroke of the brake operating member does not suddenly increase and the driver does not feel uncomfortable. In addition, since the hydraulic pressure of the brake operating device is prevented from decreasing when the vehicle is stopped, it is possible to prevent the braking force from becoming insufficient.

Further, according to the second aspect of the present invention, the flow of the brake fluid from the third fluid pressure chamber of the fluid pressure control valve to the servo fluid pressure generating device can be prevented, so that the operating force of the brake operating member increases while the vehicle is stopped. Even if this happens, the stroke of the brake operating member does not suddenly increase, and it is possible to avoid making the driver feel uncomfortable.

According to the third aspect of the present invention, since it is not necessary to supply the brake fluid from the brake operation-compatible hydraulic pressure generator or the brake actuator to the servo hydraulic pressure generator, the hydraulic pressure of the servo hydraulic pressure generator is stopped when the vehicle is stopped. Even if the pressure drops, it becomes easy to prevent the brake fluid from flowing out from the brake operation-compatible hydraulic pressure generating device and the brake operating device, and it becomes easy to solve the problem of a sudden increase in the stroke of the brake operating member. In addition, since the amount of brake fluid in the servo hydraulic pressure generator will not become insufficient, as will be described in detail in the section of the embodiment, the position of the shift lever is moved forward (D) while the brake operating member is stopped while being operated. )
It is possible to prevent or reduce rattling in the servo hydraulic pressure generation device when the hydraulic pressure is changed from reverse to reverse (R).

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A hydraulic brake device, which is an embodiment common to the first to third inventions, will now be described in detail with reference to the drawings. In FIG. 1, 10 is a brake pedal as a brake operating member, and 12 is a master cylinder as a brake operation-corresponding hydraulic pressure generator that generates hydraulic pressure according to the pedaling force of the brake pedal 10. Reference numerals 16 and 17 are calipers provided with wheel cylinders that actuate brakes that suppress the rotation of the front wheels and the rear wheels.

First, the caliper 16 provided on the front wheel side will be described. In FIGS. 7 and 8, reference numeral 18 is a disc rotor for the front wheels. A disc rotor (hereinafter, simply referred to as a rotor) 18 is fixed to an axle hub 19 by a bolt (not shown) so as not to rotate relative to the axle hub 19. A spindle 20 is integrally extended from the center of the axle hub 19, and a steering knuckle 22 serving as a fixing member is provided.
It is held so that it can rotate relative to it. Therefore, the rotor 18 rotates integrally with the spindle 20 and the axle hub 19 around the axis L.

The caliper 16 is placed over the rotor 18.
Is provided. The caliper 16 is a so-called opposed type, and is provided with two pairs of wheel cylinders (hereinafter, simply referred to as cylinders) 24 and 26 with a rotor 18 interposed therebetween, and pistons 28 and 30 are liquid-tight and slidable respectively. Mating is possible. An inner pad 32 is arranged between the two pistons 28 and the rotor 18, and an outer pad 34 is arranged between the two pistons 30 and the rotor 18. The inner pad 32 and the outer pad 34 are supported on their respective back plates 36 and 38 by the caliper 16 so as to be movable in the axial direction of the rotor 18. A pair of pad pins 40 fixed to the caliper 16 are inserted through the back plates 36 and 38 to prevent the pads 32 and 34 from moving in the rotor radial direction.

Hydraulic chambers 41, 42 of each cylinder 24, 26
Is connected to the master cylinder 12 via the control valve 44 by the liquid passages 50, 52 as shown in FIG. 1, and is provided adjacent to the caliper 16 by the liquid passages 52, 54, as shown in FIG. It is connected to the servo hydraulic pressure generating chamber 48 of the pressure generating device 46. Each hydraulic chamber 41, 42
The brake fluid is supplied to the pistons 28, 3
0 is advanced toward the rotor 18, and both pads 3
2, 34 are pressed against the rotor 18. Further, a stroke simulator 56 as a hydraulic pressure rapid increase suppressing means for suppressing a rapid increase in the hydraulic pressure in the hydraulic pressure chambers 41 and 42 is attached in the middle of the liquid passage 50 connecting the master cylinder 12 and the control valve 44. .

The caliper 17 provided on the rear wheel side is arranged so as to straddle a rotor 58 which rotates integrally with the rear wheel. Since the caliper 17 is almost the same as the caliper 16, detailed description thereof will be omitted, but the caliper 17 includes a pair of cylinders and a pair of hydraulic chambers. The hydraulic chamber has a fluid passage 52 through a proportioning valve 60.
The master cylinder 12 is connected to the cylinder.
Or the hydraulic pressure obtained by reducing the hydraulic pressure of the servo hydraulic pressure generator 46 is supplied. As described above, since the cylinder of the caliper 17 is made to communicate with the servo hydraulic pressure generator 46, it is not necessary to provide a dedicated servo hydraulic pressure generator on the rear wheel side.

As shown in FIG. 1, the caliper 16 is connected to the steering knuckle 22 by two links 70. As shown in FIG. 8, notches 71 extending in the radial direction of the rotor 18 are formed at two locations on the caliper 16 that are eccentric from the axis L (see FIG. 7) and are separated in the circumferential direction. 2 for knuckle 16
Individual protrusions 73 (only one protrusion is shown in FIG. 7) are formed. The protrusions 73 are eccentric from the axis L and extend outward in the radial direction of the rotor 18 at positions separated from each other in the circumferential direction of the rotor 18.

Each of the two links 70 is inserted into the notch 71 at one end thereof, and is connected by a pin 75 so as to be rotatable about an axis parallel to the axis L. The other end of each link 70 has a yoke shape as shown in FIG.
Is rotatably connected about an axis parallel to. The pin 76 connecting each of the two links 70 to the steering knuckle 22 is located on one arc centering on the axis L, and the two pins 75 connecting to the caliper 16 are centering on the axis L and having a radius smaller than the one arc. It is located on another large arc. In addition, each link 70 has a rotor 18
Extend substantially radially. Therefore, caliper 1
6 is attached to the steering knuckle 22 so as to be rotatable substantially in the circumferential direction of the rotor 18 by two links 70 and two pins 75 and 76. On the other hand,
The rear caliper 17 is fixed to the non-rotating member in a state where the circumferential movement of the rotor 54 is blocked.

The servo hydraulic pressure generator 46 has a servo cylinder 78 and a servo cylinder drive member 80 (hereinafter abbreviated as drive member 80) as shown in FIGS. As shown in FIG. 2, the cylinder housing 82 of the servo cylinder 78 has a cylindrical member 84 and a cap 86 screwed to one longitudinal end thereof. As shown in FIGS. 5 and 6, a protrusion 88 that protrudes upward (outward in the radial direction of the rotor 18) is provided at an intermediate portion in the axial direction of the cylindrical member 84, and a front side (rotation of the rotor 18). A mounting portion 90 protruding in a direction parallel to the axis) and a mounting portion 92 protruding downward (inward in the radial direction of the rotor 18) are provided, and the cylinder housing 8 is provided.
Reference numeral 2 denotes mounting portions 90 and 92, which are fixed to a mounting portion (not shown) provided on the steering knuckle 16 in a posture in which a center line thereof extends in a direction in contact with a circle centered on the rotation axis of the rotor 18.

In the cylindrical member 84, the first piston 1
00 and the second piston 102 are sealed by cup seals 104 and 106, respectively, and are fitted liquid-tightly and slidably, and the servo hydraulic pressure generating chamber 48 is formed between the pistons 100 and 102. . The servo hydraulic pressure generating chamber 48 is connected to the control valve 44 at the servo hydraulic pressure port 107 formed in the mounting portion 90.

The first and second pistons 100, 102 are urged by springs 108 disposed in the servo hydraulic pressure generating chamber 48 in directions away from each other. First piston 1
00 is located on the caliper 16 side, the second piston 102 is located on the side away from the caliper 16, and the spring 108
The movement of the first piston 100 by the movement of the first piston 100 is caused by the radially inward flange portion 110 formed at the open end of the cylindrical member 84.
The movement of the second piston 102 is restricted by the radially inward flange portion 112 provided on the cap 86.
It is regulated by. Also, the first and second pistons 10
Engaging projections 114 and 116 are concentrically formed on the end surfaces of the Nos. 0 and 102 facing the servo hydraulic pressure generating chamber 48 side, respectively.
In the state where both of the two abut on the flange portions 110 and 112, the engaging protrusions 114 and 116 are located in the openings 118 and 120 formed in the flange portions 110 and 112, respectively.

The drive member 80 includes a plate-shaped back plate portion 124 having a width wider than the diameter of the cylindrical member 84 of the cylinder housing 82, and one end of the back plate portion 124 in the longitudinal direction toward the center of the rotor 18. To the center of the rotor 18, and a plate-shaped mounting portion 126 that is extended to the rotor 18 and is parallel to the plate surface of the rotor 18.
And a plate-shaped arm portion 128 that is parallel to the rotation axis of the. The drive member 80 is arranged in a state of straddling the cylinder housing 82 from the outer peripheral side of the rotor 18, and the arm 13 extended from the link 70 in an elongated hole 129 formed in the mounting portion 126.
0 (see FIG. 1) is rotatably connected by a pin 132 about an axis parallel to the axis L. The mounting portion 126 and the arm portion 128 are opposed to the first piston 100 and the second piston 102, respectively, and the opposing end surfaces 134 and 136 respectively engage with the engaging projection 13 as an operating portion.
8,140 are projected. The engagement protrusion 138 is shorter than the engagement protrusion 140. The reason will be described later.

Further, an elongated hole 142 extending parallel to the center line of the cylinder housing 82 is formed in the back plate portion 124,
Two bolts 144 are screwed through the elongated holes 142 to the protrusions 88 provided on the cylinder housing 82, and the movement of the drive member 80 is guided by the elongated holes 140 and the bolts 142.

The control valve 44 will be described. 9 to 1
As shown in FIG. 1, the control valve 44 includes a hydraulic pressure control valve 150 and an opening / closing valve 152. The hydraulic pressure control valve 150 and the opening / closing valve 152 are configured in the same valve housing 154. These are a piston 156 that also serves as a valve element of the hydraulic pressure control valve 150 and a piston 158 that also serves as a valve opening member of the opening / closing valve 152. Are provided so as to extend in directions orthogonal to each other.

The valve housing 154 has a first port 160 communicating with the master cylinder 12, a second port 162 communicating with the hydraulic chambers 41, 42 of the cylinders 24, 26 of the caliper 16, and a servo hydraulic pressure of the servo cylinder 78. A third port 164 communicating with the port 107 and a fourth port 166 communicating with the reservoir 165 are formed. Further, the valve housing 154 is provided with a first port 160 and a second port 162, and the hydraulic control valve 150.
A bypass passage 168 for bypassing and connecting the second port 162 and the third port 164 is formed, and a bypass passage 170 for connecting the hydraulic pressure control valve 150 by bypass is formed. In the middle of the bypass passage 168, A check valve 172 is provided, and the opening / closing valve 1 is provided in the middle of the bypass passage 170.
A check valve 174 is provided with 52. Further, the liquid passage 1 connecting the third port 164 and the fourth port 166.
76 is formed, and a check valve 178 is provided in the middle of the liquid passage 176.

The check valve 172 allows the brake fluid to move from the master cylinder 12 to the hydraulic chambers 41 and 42 when the hydraulic pressure in the master cylinder 12 is higher than the hydraulic pressure in the hydraulic chambers 41 and 42. However, if the hydraulic pressure in the hydraulic pressure chambers 41, 42 becomes higher than the hydraulic pressure in the master cylinder 12, it will be in a closed state to prevent movement of the brake fluid. Therefore, in the initial stage of the operation of the brake pedal 10, the brake fluid flows from the master cylinder 12 through the fluid pressure control valve 150 to the fluid pressure chambers 41 and 4.
2 to the bypass passage 168, the check valve 1
It is supplied even after 72, and the delay in braking effectiveness is avoided.

The check valve 174 includes the caliper hydraulic chambers 41, 4
The flow of the brake fluid from the No. 2 to the servo hydraulic chamber port 107 is allowed, but the reverse flow is blocked. Further, the check valve 178 allows the flow of the brake fluid from the reservoir 165 to the servo hydraulic pressure chamber port 107, but blocks the flow in the opposite direction.
When is lower than the atmospheric pressure, the brake fluid is supplied from the reservoir 165 to the servo fluid pressure generating chamber 48.

The valve housing 154 is further provided with a cylindrical fitting hole 180 and a first hydraulic pressure chamber 181 which communicates with the bottom of the fitting hole 180. The first hydraulic pressure chamber 181. Through the liquid passage 168 to the first port 16
It is connected to 0.

In the fitting hole 180, the hydraulic pressure control valve 1
An auxiliary housing 182 that constitutes the housing of 50 is fitted and fixed by a screw member 184. The auxiliary housing 182 is a cylindrical member having a cylinder bore 186 formed in the center thereof, and the second hydraulic chamber 194 and the third hydraulic chamber 196 are formed by through holes formed in the radial direction.
Are formed. The second hydraulic chamber 194 is connected to the second port 162 via the liquid passage 198, and the third hydraulic chamber 196 is connected.
Is connected to the third port 164 via the liquid passage 200.

A check valve 202 is provided in the liquid passage 200, as shown in FIG. Check valve 202
Allows the flow of the brake fluid from the third port 164 to the third hydraulic chamber 196, but blocks the reverse flow. That is, when the servo hydraulic pressure is generated in the servo hydraulic pressure generating chamber 48, the brake fluid in the servo hydraulic pressure generating chamber 48 is supplied to the third hydraulic pressure chamber 196 via the check valve 202, and the third hydraulic pressure chamber 196 is supplied. The hydraulic pressure of the pressure chamber 196 is increased. As will be described later, when the hydraulic pressure control valve 150 is in a pressure increasing state that allows the third hydraulic pressure chamber 196 and the second hydraulic pressure chamber 194 to communicate with each other, the brake fluid in the third hydraulic pressure chamber 196 is hydraulically controlled. The caliper hydraulic pressure is supplied to the caliper hydraulic pressure chambers 41 and 42 via the valve 150, and the caliper hydraulic pressure is increased. However, since the check valve 202 blocks the supply of the brake fluid from the third hydraulic pressure chamber 196 to the servo hydraulic pressure generation chamber 48, the hydraulic pressure control is performed when the hydraulic pressure of the servo hydraulic pressure generation chamber 48 is low. Even if the valve 150 is in a pressure increasing state, the brake fluid is not supplied from the caliper fluid pressure chambers 41 and 42 to the servo fluid pressure generating chamber 48 via the fluid pressure control valve 150.

The cylinder bore 186 of the auxiliary housing 182 is a stepped hole having a large-diameter hole portion and a small-diameter portion hole portion. Passages 206 and 208 are formed. In addition, a movement limit defining member 212 is provided in the opening of the small diameter hole opposite to the large diameter hole. The piston 156 fitted in the cylinder bore 186 is also a stepped piston having a large diameter portion 216 and a small diameter portion 218, and the large diameter portion 2
16 is fitted in the large diameter hole portion, and the small diameter portion 218 is fitted in the small diameter hole portion. A central hole 220 is formed at the center of the small diameter portion 218 of the piston 156, and the large diameter portion 2 is also formed.
Circular groove-shaped liquid passages 222 and 224 are formed on the outer peripheral surface of the small-diameter portion 218 and the stepped portion of the small-diameter portion 218.

A shaft portion 232 is provided at the center of the movement limit defining member 212, and the shaft portion 232 serves as the piston 15.
6 is fitted into the center hole 220. Shaft 23
2 has a stepped shape, and the stepped portion and the center hole 220
A spring 236 is arranged between the bottom surface and the bottom surface of the spring.
The spring 236 urges the piston 156 in the backward direction (rightward in the drawing). The forward end of the piston 156 is defined by the movement limit defining member 212. A plurality of through holes 237 are formed in the movement limit defining member 212, and the through holes 237 communicate with the tool engaging hole 239 of the hexagonal cross section of the screw member 184. for that reason,
The space between the piston 156 and the movement limit defining member 212 is open to the atmosphere.

The liquid tightness between the piston 156 and the cylinder bore 186 is maintained by making the clearance between the piston 156 and the cylinder bore 186 as small as several microns or less, and the seal member is omitted to reduce the sliding resistance of the piston 156. There is. That is, in order to move the piston 156, a force corresponding to the sum of the set load of the spring 236 and the sliding resistance is required, but in the present embodiment, the latter force is small. Therefore, the piston 156
Is the hydraulic pressure in the first hydraulic chamber 181 (master cylinder hydraulic pressure Pm
) Becomes a size approximately corresponding to the set load of the spring 236, it is moved.

The piston 156 and the cylinder bore 18 are
6 cannot be sufficiently prevented from leaking due to insufficient liquid-tightness with 6, the screw members 184 and 238 and the movement limit defining member 212 are integrated into a plug and the plug and the housing 154 are integrated. A seal member may be provided therebetween, and the space between the piston 156 and the plug may be communicated with the fourth port 166 by the liquid passage.

On the other hand, liquid passages 240 and 242 are formed in the large diameter portion 216 of the piston 156. Liquid passage 24
0 and 242 are communicated with the first hydraulic chamber 181 described above,
The hydraulic pressure Pm of the master cylinder 12 is made to act.

As shown in FIG. 11, the on-off valve 152 provided in the middle of the bypass passage 170 has a piston 158,
A spring 252 as a biasing means is provided. The clearance between the piston 158 and the cylinder bore 256 is as small as a few microns or less, so that liquid tightness can be maintained without a seal member. One end of the cylinder bore 256 is communicated with the screw hole 258, and the screw hole 258 is closed by the plug 260. The space formed inside the plug 260 is communicated with the atmosphere through the through hole 262 of the plug 260 to form an atmospheric pressure chamber 264.
A large-diameter head portion 266 of the piston 158 is accommodated in 64. The spring 252 is disposed between the head 266 and the plug 260, and the piston 158 is connected to the hydraulic chamber 2.
It is biased to the 74 side. The hydraulic chamber 274 is communicated with the first port 160 by a liquid passage 276 so that the piston 158 receives the master cylinder hydraulic pressure Pm.

The piston 158 is also the piston 15
Similar to 6, when the hydraulic pressure in the hydraulic chamber 274 (master cylinder hydraulic pressure Pm) becomes a magnitude P ₀ (see FIG. 17) which corresponds to the set load of the spring 252, the hydraulic chamber 274 is moved.
When the liquid tightness between the piston 158 and the cylinder bore 256 is insufficient, the plug 260 does not have the through hole 262, and the plug 260 and the housing 15 are not provided.
A seal member may be provided between the first port 160 and the first port 160, and the liquid passage may communicate with the first port 160.

An annular groove-shaped liquid passage 288 is formed in the middle of the piston 158. In the original position shown in the figure, the liquid passage 288 is in a position where it coincides with the bypass passage 170, and the bypass passage 170 is maintained in a communicating state.
When the hydraulic pressure in the hydraulic pressure chamber 274 becomes higher than the set load of the spring 252, the piston 158 is moved to the atmospheric pressure chamber 264 side against the urging force of the spring 252, and the liquid passage 288 is disengaged from the bypass passage 170, thereby bypassing the bypass passage 170. Passage 1
70 is cut off. The set load of the spring 252 is set low. For example, a substantial braking effect is generated in the caliper 16 and the bypass passage 170 is blocked before the servo hydraulic pressure generation device 46 starts to generate servo hydraulic pressure. As shown, the bypass passage 170 is cut off at a master cylinder hydraulic pressure P ₀ which is considerably lower than the servo hydraulic pressure starts to be generated.

As shown in FIG. 12, the stroke simulator 56 provided in the middle of the liquid passage 50 of FIG. 1 has a bottomed cylindrical housing 320. Housing 3
A cylinder bore 322 is formed in the cylinder 20, and a piston 324, a stopper 326, a spring 328, etc. are arranged in the cylinder bore 322. In addition, the housing 32
The set load adjusting device 332 is attached to the opening 330 of 0, and the ports 336 and 33 are attached to the bottom portion 334.
7 are formed. The master cylinder 12 is connected to the port 336, and the port 337 is closed by the air bleeder 338.

The end surface of the piston 324 on the bottom 334 side is
An outer peripheral portion is projected to form an annular protrusion 340. A hydraulic chamber 342 is provided between the protrusion 340 and the bottom 334.
Is formed and is in communication with the port 336. Since the hydraulic pressure in the master cylinder 12 is supplied to the hydraulic chamber 342, the hydraulic pressure in the hydraulic chamber 342 is the hydraulic pressure P in the master cylinder 12.
Same as m. A first atmospheric pressure chamber 344 is formed between the piston 324 and the stopper 326.
An O-ring 346 attached to the outer peripheral surface of the is closed from the hydraulic chamber 342.

The end surface of the piston 324 on the stopper 326 side has an outer peripheral portion projected annularly so that the retainer 35 is formed.
It is set to 0. On the other hand, the stopper 326 has a stepped shape having a large diameter portion and a small diameter portion, and a spring 328 is arranged between the step portion and the retainer 350. The spring 328 biases the piston 324 in a direction to press it against the bottom portion 334, and
An original position (hereinafter, referred to as a retracted end position) is defined by the protrusions 340 of 24 contacting the bottom portion 334.

A fitting hole 356 is formed in the center of the end surface of the stopper 326 opposite to the piston 324, and a spherical transmission member 358 is fitted in the fitting hole 356. The set load adjusting device 332 includes a cover 366 including a female screw on the inner peripheral portion thereof and a plurality of through holes 364 extending axially in the circumferential direction, and an adjusting screw 368 screwed to the cover 366. It includes. The end surface of the adjusting screw 368 is brought into contact with the transmitting member 358, and the movement of the adjusting screw 368 is transmitted to the stopper 326 via the transmitting member 358.

Stopper 326 and set load adjusting device 33
A second atmospheric pressure chamber 370 is formed between
It is open to the atmosphere via 64. In addition, the stopper 32
6, a plurality of through holes 372 extending in the axial direction are provided, and the first atmospheric pressure chamber 344 and the second atmospheric pressure chamber 370 are communicated with each other.

When the adjusting screw 368 is moved to the right in the drawing by rotating, the stopper 326 is moved to the right accordingly, and the distance between the stopper 326 and the piston 324 is narrowed. Spring 328
Is compressed, the set load increases, and the movable amount of the piston 324 decreases. Conversely, adjusting screw 368
Is moved to the left by rotating in the opposite direction to the above, the stopper 326 is moved to the left by the biasing force of the spring 328. Spring 32
No. 8 is allowed to extend, the set load decreases and the movable amount of the piston 324 increases.

While the hydraulic pressure of the hydraulic chamber 342 is smaller than the set load of the spring 328, the piston 324 is kept at the retracted end position (right end position), but the hydraulic pressure of the hydraulic chamber 342 is lower than the set load of the spring 328. If it gets bigger, piston 3
The forward movement (movement to the left) of 24 is started. The piston 324 is advanced according to the stroke of the brake pedal 10. The amount of movement is smaller as the spring constant is larger and larger as the spring constant is smaller when the pedaling force is the same. As will be described later, the set load of the spring 328 is such that the master cylinder 12 hydraulic pressure increases as the pedaling force of the brake pedal 10 increases, and the brake fluid in the second hydraulic pressure chamber 194 of the hydraulic pressure control valve 150 increases. The value is set to such a value that the forward movement of the piston 324 is started when the hydraulic pressure in the hydraulic chamber 342 is rapidly increased by backflowing to the passage 50 (on the master cylinder 12 side).

The operation of the hydraulic brake device constructed as above will be described. 14 to 16 are views showing the operation by simplifying the structure of the hydraulic control valve 150. Here, the fluid pressure chambers 41, 42 of the front wheel side caliper 16 are
The situation where the hydraulic pressure is supplied to the hydraulic pressure will be described, and the description regarding the situation where the hydraulic pressure is supplied to the hydraulic chamber of the caliper 17 on the rear wheel side will be omitted. While the vehicle is traveling, the rotor 18 rotates with the wheels,
In the servo hydraulic pressure generator 46, the first and second pistons 100 and 102 of the servo cylinder 78 both come into contact with the flange portions 110 and 112 as shown in FIG.
The engagement protrusions 138, 140 of the drive member 80 are in a neutral state in which they are close to the engagement protrusions 114, 116 of the first and second pistons 100, 102, and servo hydraulic pressure is generated in the servo hydraulic pressure generation chamber 48. I haven't. Further, as shown in FIG. 14, in the hydraulic control valve 150, the piston 156 is in the original position (retraction end position) by the urging force of the spring 236, and the cylinders 24 and 26 of the caliper 16 are moved to the master cylinder 12.
Is in communication with. The hydraulic pressure control valve 150 is in a communicating state. On the other hand, in the on-off valve 152, the liquid passage 28
8 is in the open state in conformity with the bypass passage 170, and the bypass passage 170 is in communication. The piston 324 of the stroke simulator 56 is at the retracted end position.

When the driver depresses the brake pedal 10, the brake fluid from the master cylinder 12 in the hydraulic control valve 150 is supplied with the brake fluid from the first port 160, the first hydraulic chamber 181, the fluid passages 240, 242, 206. , 22
2, second hydraulic chamber 194, liquid passage 198, second port 16
It is supplied to the cylinders 24 and 26 of the caliper 16 via the line 2. In addition, the bypass passage 16 is provided in the cylinders 24 and 26.
8 and the check valve 172, the brake fluid of the master cylinder 12 is supplied. As described above, in the present embodiment, since the bypass passage 168 and the check valve 172 are provided, the cylinders 24 and 2 are provided at the beginning of the stepping operation.
The brake fluid supplied to 6 flows at a sufficient flow rate, and the delay in braking effectiveness is reduced. At this stage, the hydraulic pressure Pm of the master cylinder 12 and the hydraulic pressure Pw of the cylinders 24 and 26 (hereinafter referred to as the caliper hydraulic pressure Pw) are equal (Pm = P
w).

In the on-off valve 152, while the master cylinder hydraulic pressure Pm is smaller than the set value P ₀ , the piston 158 is kept in the original position in the figure, the bypass passage 170 is in the communicating state, and the servo hydraulic pressure Ps is also shown. As shown in 17, the hydraulic pressure rises with the master cylinder hydraulic pressure Pm, but since the set value P ₀ is very small, the hydraulic pressure in the hydraulic chamber 274 is lower than the set value P ₀ while the depression force of the brake pedal 10 is very small. As the height rises, the piston 158 is moved against the biasing force of the spring 252. The liquid passage 288 is the bypass passage 17
Since it deviates from 0 and the bypass passage 170 is blocked, the servo hydraulic pressure Ps stops increasing as shown in FIG. In the stroke simulator 56,
While the hydraulic pressure in the hydraulic chamber 342 is smaller than the set load of the spring 328, the piston 324 does not move forward and is kept at the backward end position.

When the caliper hydraulic pressure Pw is supplied to the cylinders 24 and 26, the pads 32 and 34 are pressed against the friction surfaces on both sides of the rotor 18 by both pistons 28 and 30, and braking is performed. At this time, the accompanying torque in the rotation direction of the rotor 18 (the direction indicated by the solid arrow in FIG. 1) acts on the caliper 16, and the pair of links 70 causes the rotor 18 to move.
At a position eccentric from the axis L, the small angle rotation is performed in a plane perpendicular to the axis L. As described above, the pair of links 70
Since it extends substantially in the radial direction of the rotor 18, if the link 70 rotates from that position by a small angle, the caliper 16 will rotate about the axis L of the rotor 18. That is, as shown in FIG. 13, the gap t between the front end of the caliper 16 and the outer peripheral surface of the rotor 18 and the rear of the caliper 16 before the rotation indicated by the solid line and after the angle α rotation indicated by the two-dot chain line. There is almost no difference in the clearance c between the end and the outer peripheral surface of the rotor 18. By thus moving the caliper 16 substantially in the circumferential direction of the rotor 18, it is possible to favorably avoid the front end portion coming into contact with the outer peripheral surface of the rotor 18 and the rear end portion coming into contact with the wheel disk. .

While the vehicle is moving forward, the rotor 18 rotates in the direction shown by the solid arrow in FIG. 1, and the accompanying torque causes the caliper 16 to rotate in the same positive direction as the rotation direction of the rotor 18. With the rotation of the caliper 16, the driving member 80
Is moved in the forward direction of the vehicle by moving the second piston 102 toward the first piston 100 side against the urging force of the spring 108, and the volume of the servo hydraulic pressure generating chamber 48 is reduced. As a result, the servo hydraulic pressure Ps is generated. FIG. 3 shows a state in which the second piston 102 is moved closest to the first piston 100 side. In this state, the volume of the servo hydraulic pressure generating chamber 48 is reduced most, and the maximum servo hydraulic pressure Ps is generated. The second piston 102 is actually the caliper 1
6 is moved to a position where a servo hydraulic pressure that balances the pulling force of the drive member 80 based on the rotation of 6 is generated.

This servo hydraulic pressure Ps is the servo hydraulic pressure port 1
Is supplied to the third port 164 of the control valve 44 via 07,
Further, it is supplied to the third hydraulic chamber 196 via the check valve 202. The connecting end of the link 70 to the caliper 16 slightly moves in the radial direction of the rotor 18 when the link 70 rotates, and the arm 130 also moves accordingly.
30 is connected to the mounting portion 126 of the driving member 80 by the elongated hole 129 and the pin 132, so that the driving member 8
0 moves in a direction in contact with a circle around the rotation axis of the rotor 18 while allowing the movement of the arm 130.

On the other hand, in the hydraulic control valve 150, when the master cylinder hydraulic pressure Pm increases and the equation Pm.Ar> F ₀ + f (1) is satisfied, the piston 156 starts to move forward. A
r is the small diameter portion 2 of the piston 156, as shown in FIG.
18 is a sectional area of 18, F ₀ is a set load of the spring 236, and f is a frictional resistance of the piston 156. Ah, which will be described later, is the cross-sectional area of the large-diameter portion 216, and F ₁
Is the urging force of the spring 236 at the moment when the communication between the liquid passage 206 and the liquid passage 222 is cut off, and F ₂ is the spring 2 at the moment when the liquid passage 224 starts communicating with the second hydraulic chamber 196.
36 urging forces. The piston 156 is the spring 23.
By slightly advancing against the biasing force of 6, as shown in FIG. 15, the communication between the first port 160 and the second port 162 is cut off. That is, the master cylinder hydraulic pressure Pm and the servo hydraulic pressure Ps are not supplied to the cylinders 24 and 26, and the cylinders 24 and 26 are shut off. This cutoff state is maintained while the formula F ₁ −f ≦ Pm · Ah−Pw (Ah −Ar) ≦ F ₂ + f (2) holds.

[0063] Further the master cylinder pressure Pm increases with the brake pedal 10 is depressed, if satisfied equation Pm · Ah> Pw (Ah -Ar ) + F 2 + f ··· (3) is, as shown in FIG. 16 Then, the piston 156 further advances and enters a pressure increasing state in which the second port 162 and the third port 164 communicate with each other. Therefore, the third port 1
The servo hydraulic pressure Ps supplied from 64 is the hydraulic passage 200, the check valve 202, the third hydraulic chamber 196, the hydraulic passages 224, 20.
It is supplied to the cylinders 24 and 26 of the caliper 16 via 8, 222, the second hydraulic chamber 194 and the second port 162, and the pressing force of the pads 32 and 34 on the rotor 18 is increased.

[0064] The supply of servo pressure Ps, formula _{Pw (Ah -Ar) + F 2} > Pm · Ah + f if (4) is satisfied, the second port 1 the piston 156 is retracted
62 is cut off from the third port 164, and the cutoff state is restored. The caliper hydraulic pressure Pw is controlled to be higher than the master cylinder hydraulic pressure Pm and substantially proportional to the master cylinder hydraulic pressure Pm.

That is, in the hydraulic pressure control valve 150,
Before the equation (1) is satisfied, that is, when the hydraulic pressure Pm of the master cylinder is {(F ₀ + f) / Ar} (the hydraulic pressure P ₁ in FIG. 17) or less, the piston 156 is at the backward end position. , The first port 160 and the second port 162 are in communication with each other in the first state. The hydraulic pressure of the second hydraulic chamber 194 is kept equal to the hydraulic pressure of the first hydraulic chamber 181, that is, the caliper hydraulic pressure Pw is kept equal to the master cylinder hydraulic pressure Pm. In this state, the relationship between the master cylinder hydraulic pressure Pm, the caliper hydraulic pressure Pw, and the servo hydraulic pressure Ps is as shown in the area surrounded by the thin line in the graph of FIG. However, in FIG. 17, in order to avoid complication, the influence of the change in the biasing force of the spring 236 and the hysteresis based on the frictional resistance f are omitted.

When the hydraulic pressure Pm of the master cylinder becomes higher than the set value P ₁ and the equation (1) is satisfied, the piston 156 starts to move forward, and eventually the second port 162 and the third port 1
64, the second state is established in which communication is established with 64, and then both ports are shut off so that the caliper hydraulic pressure Pw is higher than the master cylinder hydraulic pressure Pm as shown in FIG. The height is controlled according to Pm. The caliper fluid pressure Pw is increased with a gradient determined by the areas of the cross-sectional area Ar of the small diameter portion 218 and the cross-sectional area Ah of the large diameter portion 216 of the piston 156, and is large with respect to the increase amount ΔPm of the master cylinder fluid pressure Pm. Increase in pressure Pw Δ
Pw will be obtained.

The transition from the first state to the second state is performed after the servo hydraulic pressure Ps becomes higher than the master cylinder hydraulic pressure Pm. As described above, the servo hydraulic pressure Ps is generated by pressing the pads 32 and 34 against the friction surface of the rotor 18 by the caliper hydraulic pressure Pw to rotate the caliper 16 and applying a tensile force to the drive member 80. The volume of the servo hydraulic pressure generating chamber 48 is reduced and generated. When the caliper hydraulic pressure Pw is small and the accompanying torque of the caliper 16 is small, no hydraulic pressure is generated in the servo hydraulic pressure generating chamber 48. Therefore, the set value P ₁ is equal to the caliper hydraulic pressure after the hydraulic pressure Ps _{1 which} is greater than the master cylinder hydraulic pressure Pm is generated in the servo hydraulic pressure generating chamber 48 (at this point, the caliper hydraulic pressure and the master cylinder hydraulic pressure are equal to each other). The hydraulic pressure is equal).

The above-mentioned check valve 202 is provided with the third port 164.
Is higher than the hydraulic pressure in the third hydraulic chamber 196, that is, when the servo hydraulic pressure Ps is generated in the servo hydraulic pressure generating device 46, the third hydraulic pressure chamber 164 is used. Since the brake fluid is allowed to move to 196, at the time when the hydraulic control valve 150 shifts to the second state,
Servo hydraulic pressure Ps is supplied to the third hydraulic chamber 196.

The sectional areas of the first and second pistons 100, 102 in the servo hydraulic pressure generator 46 are such that the servo hydraulic pressure P in the servo hydraulic pressure generating chamber 48 is higher than the master cylinder hydraulic pressure Pm.
It is determined that s can occur. Also, a check valve 178
Since the flow of the brake fluid from the servo hydraulic chamber 48 to the reservoir 165 is blocked, the brake fluid in the servo hydraulic chamber 48 never flows out to the reservoir 165.

When the hydraulic pressure control valve 150 shifts from the first state to the second state, as described above, the brake fluid is supplied from the servo hydraulic pressure generating chamber 48 to the second hydraulic chamber 194.
The hydraulic pressure in the second hydraulic chamber 194 suddenly increases. as a result,
Formula (4) is established, the piston 156 is retracted, and the brake fluid in the first hydraulic chamber 181 flows backward to the fluid passage 50 side. As a result, in the stroke simulator 56,
The hydraulic pressure in the hydraulic chamber 342 becomes larger than the hydraulic pressure corresponding to the set load of the spring 328, and the piston 324 is advanced. The stroke simulator 56 absorbs a part of the backflowing brake fluid, and as a result, as shown in FIG. 18, the master cylinder fluid pressure when the fluid pressure control valve 150 changes from the first state to the second state. P
The sudden increase in m is reduced.

FIG. 18 shows the relationship between the time and the master cylinder hydraulic pressure Pm when the pedal effort of the brake pedal 10 is increased at a constant speed. In the conventional hydraulic brake device, since the stroke simulator 56 is not provided, when the hydraulic pressure control valve 150 shifts from the first state to the second state, the master cylinder hydraulic pressure rapidly increases as shown by the solid line. However, by providing the stroke simulator 56, the rapid increase amount becomes small as indicated by the broken line or the one-dot chain line.

Then, as described above, the hydraulic pressure control valve 150
In the above, since the hydraulic pressure in the second hydraulic chamber 194 is controlled in accordance with the master cylinder hydraulic pressure Pm, the rapid increase in caliper hydraulic pressure Pw is also suppressed as shown in FIG. Therefore, the amount of increase in the braking force at the time of the above-mentioned transition of the hydraulic pressure control valve 150 is small, and the controllability of the braking force is improved. That is, the controllability of the braking force is improved when the pedaling force of the brake pedal 10 is relatively small.

Piston 3 of stroke simulator 56
24 is advanced with the stroke of the brake pedal 10. If the stroke simulator 56 is not provided, when the hydraulic control valve 150 shifts from the first state to the second state, the first hydraulic chamber 181 and the second hydraulic chamber 1
Since the increase in the stroke of the brake pedal 10 is blocked by the disconnection with the brake pedal 94, as shown in FIG. 20, the stroke hardly increases even when the pedaling force increases, and the brake feeling deteriorates and the braking force is reduced. There was a problem of poor controllability of power. On the other hand, in the present embodiment, since the stroke simulator 56 is provided, even if the communication between the first hydraulic pressure chamber 181 and the second hydraulic pressure chamber 194 is interrupted, the pedaling force of the brake pedal 10 is responded to. It is possible to increase the stroke, suppress a decrease in brake feeling, and improve the controllability of the braking force. 18 to 20, when the set load of the spring 328 is small, the second hydraulic chamber 1 is larger than when the set load of the spring 328 is large.
It is clear that when the spring constant is small, the effect of suppressing the rapid increase in the hydraulic pressure of 94 is large, and the feeling of stepping is softer than when the spring constant is large.

When the depression of the brake pedal 10 is released, the master cylinder hydraulic pressure Pm decreases, and the hydraulic pressure control valve 150
, The piston 156 retracts and the caliper hydraulic pressure P
w decreases while maintaining the relationship of Pw (Ah-Ar) + F = Pm.Ah. However, F represents the urging force of the spring 236 such as F ₀ , F ₁ and F ₂ . Then, Pm · Ar <F ₀
If -f is satisfied, the piston 156 returns to the backward end position.

In the on-off valve 152, when the master cylinder hydraulic pressure Pm becomes lower than the set value P ₀ , the piston 158 is moved downward in the figure by the urging force of the spring 252. Liquid passage 288 is bypass passage 1
70, and the bypass passage 170 is communicated.

On the other hand, in the servo cylinder 78, as the caliper hydraulic pressure Pw decreases and the accompanying torque of the caliper 16 decreases, the servo hydraulic pressure Ps decreases. Then, the caliper 16 based on the biasing force of the spring 108
When the rotating torque in the opposite direction of the second piston 1 overcomes the accompanying torque, the urging force of the spring 108 causes the second piston 1 to move.
02 is returned to the position where it abuts the flange portion 112, and the drive member 80 is returned to the position where the engagement protrusion 138 is close to the engagement protrusion 114 of the first piston 100, and the caliper 16 and the link 70. Rotates in the direction of the arrow indicated by the broken line in FIG. 1 and returns to the original position.

When the second piston 102 is returned as described above, the volume of the servo hydraulic pressure generating chamber 48 increases, but this increase in volume is only after the opening / closing valve 152 is opened. For example, the brake fluid in the caliper fluid pressure chambers 41, 42 is allowed to flow in via the bypass passage 170, the opening / closing valve 152, and the check valve 174. And the on-off valve 1
When the flow rate of the brake fluid is insufficient while the valve 52 is closed or when the open / close valve 152 is open, the reservoir 1
The brake fluid of 65 is the fourth port 166 and the check valve 17
Allowed by flowing in via 8. in this way,
When the depression of the brake pedal 10 is released,
Since the on-off valve 152 is switched to the open state, the supply of the brake fluid from the caliper fluid pressure chambers 41, 42 to the servo fluid pressure generation chamber 48 via the bypass passage 170 is allowed. Further, the brake fluid in the reservoir 165 is also supplied to the servo fluid pressure generating chamber 48 as needed. As described above, since the brake fluid is supplied to the servo hydraulic pressure generation chamber 48 from both the caliper hydraulic pressure chambers 41 and 42 and the reservoir 165, the brake fluid is quickly supplied to the servo hydraulic pressure generation chamber 48. To be done.

However, the check valve 2 is provided in the middle of the fluid passage 200 connecting the third fluid pressure chamber 196 and the servo fluid pressure generating chamber 48.
02, the caliper hydraulic chambers 41, 42 are provided.
Brake fluid is not supplied to the servo hydraulic pressure generating chamber 48 via the hydraulic pressure control valve 150.

In the stroke simulator 56,
The piston 324 returns to the backward end position while returning the brake fluid to the master cylinder 12 as the master cylinder fluid pressure Pm decreases.

When the brake pedal 10 is stopped while being depressed, that is, the pads 32 and 34 are pressed against the disk rotor 18, the disk rotor 1
When the rotation of No. 8 is stopped, the hydraulic pressure in the servo hydraulic pressure generation chamber 48 decreases, and in some cases, becomes equal to or lower than the atmospheric pressure. The vehicle is decelerated by the braking force and stopped, but when the vehicle stops, it swings back. During deceleration, the inertial force of the vehicle body elastically deforms the elastic member such as the suspension provided between the vehicle body and the wheels. Move the car body relative to the wheels in the opposite direction,
The car body is moved beyond the neutral point. as a result,
A torque for rotating the wheel in the opposite direction (direction shown by a broken arrow in FIG. 1) acts on the wheel to reduce the hydraulic pressure in the servo hydraulic pressure generating chamber 48, and the rotational torque in the reverse direction is applied to the wheel. If the rolling resistance is large enough to overcome the rolling resistance, the wheel actually rotates in the opposite direction, and the caliper 16 and the drive member 80 of the servo hydraulic pressure generator 46 are rotated in the opposite direction. Along with that, the second piston 102 moves the spring 1
By being pushed back by 08, the hydraulic pressure in the servo hydraulic pressure generating chamber 48 becomes equal to or lower than the atmospheric pressure. Even when the vehicle is stopped on an uphill road surface, the rotational torque in the opposite direction acts on the wheels, and the hydraulic pressure in the servo hydraulic pressure generation chamber 48 becomes equal to or lower than atmospheric pressure.

In this case, the master cylinder hydraulic pressure Pm does not decrease because the brake pedal 10 is still depressed. Therefore, in the on-off valve 152, the piston 158 is still moved upward in the figure,
The bypass passage 170 remains blocked. Further, in the hydraulic control valve 150, the brake pedal 10
Caliper hydraulic pressure Pw
The current situation will be maintained as Hydraulic pressure control valve 15
0 means that the second hydraulic chamber 194 is kept in a holding state in which it is blocked from both the first hydraulic chamber 181 and the third hydraulic chamber 196.

In this embodiment, the servo hydraulic pressure generating chamber 4
Even if the hydraulic pressure of the hydraulic fluid 8 is lower than the atmospheric pressure, the brake fluid in the hydraulic pressure chambers 41 and 42 still remains in the bypass passage 170 or the hydraulic pressure control valve 1.
It is avoided that the fluid flows into the servo hydraulic pressure generating chamber 48 via 50, and the caliper hydraulic pressure Pw is prevented from decreasing.
Further, since the bypass passage 170 is blocked, the brake fluid is prevented from flowing out from the master cylinder 12 to the servo fluid pressure generating chamber 48. Therefore, when the brake pedal 10 is stopped while being kept depressed with a constant stepping force, the brake pedal 10 is prevented from entering and the driver's discomfort can be eliminated. Further, since the hydraulic pressures of the caliper hydraulic pressure chambers 41 and 42 are maintained at the time of stop, it is possible to prevent the braking force from becoming insufficient.

Further, in this embodiment, the check valve 202 is provided in the middle of the liquid passage 200 connecting the third port 164 and the third hydraulic chamber 196. Therefore, the piston 156 is moved forward when the driver further presses the brake pedal 10 at the time of the stop or during the stop, and the hydraulic control valve 150 causes the second hydraulic chamber 194 and the third hydraulic chamber 196 to move.
Even if the pressure is switched to a pressure increasing state in which the hydraulic fluid is communicated with the hydraulic fluid, the brake fluid in the third hydraulic pressure chamber 196 is prevented from flowing out to the servo hydraulic pressure generating chamber 48, and the hydraulic fluid in the hydraulic pressure chambers 41 and 42 is hydraulically controlled. Outflow to the servo hydraulic pressure generating chamber 48 via the valve 150 is avoided. Therefore, when stopped, the brake pedal 1
Even if the pedaling force of 0 is increased, the brake pedal 10 is prevented from entering.

Further, in the present embodiment, the servo hydraulic pressure when the position of the shift lever (not shown) is switched from D (forward) to R (reverse) after the brake pedal 10 is stopped and the vehicle is stopped. The occurrence of rattling in the generator 46 is avoided.

If the reservoir 165 is not connected to the servo hydraulic pressure generating chamber 48 and the vehicle is stopped with the brake pedal 10 being depressed, the servo hydraulic pressure generating device 46
In, the state where the first piston 100 and the second piston 102 are close to each other, that is, the state close to the state shown in FIG. In this state, when the position of the shift lever is switched from D to R and the driving force operates in the backward direction, the driving member 80 is pulled in the direction indicated by the broken line arrow in FIG. Therefore, if the reservoir 165 is not connected to the servo hydraulic pressure generation chamber 48 and the brake fluid is not supplied, the first piston 100 and the second piston 1
02 is kept close to each other, the engaging projection 110 collides with the first piston 100 to generate abnormal noise, and the impact causes the first piston 100 and the second piston 102 to move integrally. It collides with the engaging projection 140 and again produces an abnormal noise.

On the other hand, in this embodiment, since the reservoir 165 is communicated with the servo hydraulic pressure generating chamber 48, when the hydraulic pressure in the servo hydraulic pressure generating chamber 48 becomes lower than the atmospheric pressure at the time of stop, the reservoir is immediately released. Brake fluid is supplied from 165, and the first piston 100 and the second piston 102 return to the state shown in FIG. Therefore, even if the drive member 80 is pulled in the opposite direction shown by the broken line by switching the position of the shift lever from D to R, almost no abnormal noise is generated when the engaging projection 110 collides with the first piston 100. Further, since both the first piston 100 and the second piston 102 are in contact with the flanges 110 and 112, they do not move and collide with the protrusions 140 and 110.

Next, a case will be described in which the pedal effort is repeatedly increased and decreased without releasing the depression of the brake pedal 10 during braking. However, it is assumed that the pedaling force is not so small that the on-off valve 152 is switched to the open state.

As the pedal effort of the brake pedal 10 is increased, the brake fluid is supplied from the servo hydraulic pressure generating chamber 48 by the action of the hydraulic pressure control valve 150, and the hydraulic pressure chambers 41,
The hydraulic pressure of 42 is increased, and the tensile force of the drive member 80 is increased. The space between the first piston 100 and the second piston 102 is narrowed, and the servo hydraulic pressure in the servo hydraulic pressure generating chamber 48 is increased accordingly. That is, the caliper hydraulic pressure and the servo hydraulic pressure increase in accordance with the increase in the pedaling force (caliper hydraulic pressure), and the volume of the servo hydraulic pressure generating chamber 48 decreases.

On the other hand, when the pedal effort is reduced, the brake fluid in the fluid pressure chambers 41 and 42 is circulated to the master cylinder 12 by the action of the fluid pressure control valve 150, the caliper fluid pressure is reduced, and the driving member 80 is pulled. The force becomes smaller and the hydraulic pressure in the servo hydraulic pressure generating chamber 48 becomes lower. Eventually, the first piston 10
0 and the second piston 102 are separated from each other by the urging force of the spring 108, the hydraulic pressure becomes equal to or lower than the atmospheric pressure, and the brake fluid is sucked from the reservoir 165. Therefore, when the pedal effort is increased again, the servo hydraulic pressure generating chamber 4
Servo hydraulic pressure is generated at 8 without any trouble.

On the other hand, when the reservoir 165 is not connected to the servo hydraulic pressure generating chamber 48, the servo hydraulic pressure may not be generated. When the pedal effort is increased, the servo hydraulic pressure is generated as in the case of the present embodiment, but the brake fluid is transferred to the hydraulic pressure chambers 41 and 4.
2 is supplied, the volume of the servo hydraulic pressure generating chamber 48 is reduced. Then, even if the pulling force of the driving member 80 is reduced by the depression force being reduced next time, the brake fluid is not supplied to the servo fluid pressure chamber 48 because the opening / closing valve 152 remains closed. Therefore, as the pedal effort is repeatedly increased and decreased, the brake fluid in the servo hydraulic pressure generating chamber 48 may decrease, and eventually the servo hydraulic pressure may not be generated according to the pedal effort.

Next, the case where the brake pedal is depressed while the vehicle is moving backward will be described. Rotor 1 while the vehicle is retreating
8 rotates in the direction indicated by the dashed arrow in FIG.
Therefore, if the driver depresses the brake pedal, the caliper 16 causes the rotor 18 to rotate due to the accompanying torque.
Rotate in the opposite direction, which is the same as the rotation direction of the caliper 16
Drive member 80 moves in the vehicle backward direction in accordance with the rotation of
The first piston 100 is moved to the second piston 102 side. Therefore, the volume of the servo hydraulic pressure generating chamber 48 is reduced and the servo hydraulic pressure Ps is generated. FIG. 4 shows a state in which the maximum servo hydraulic pressure is generated during braking in the backward direction of the vehicle.

The servo hydraulic pressure Ps generated when the vehicle moves backward is
It becomes lower than the servo hydraulic pressure Ps generated when the vehicle moves forward. The movement limit of the drive member 80 when the vehicle moves forward is defined by the first piston 100 and the second piston 102 contacting each other before the end surface 136 of the arm 128 contacts the end surface of the cap 86, and the vehicle retreats. The movement limit of the drive member 80 at this time is defined by the end surface 134 of the mounting portion 126 contacting the end surface of the cylindrical member 84.
The lengths of the engagement protrusion 140 and the engagement protrusion 138 are determined as such, and the volume reduction amount of the servo hydraulic pressure generating chamber 48 during braking during vehicle reversing is smaller than that during vehicle forward traveling. The maximum value of the servo hydraulic pressure Pw generated when the vehicle moves backward is limited to a value lower than the maximum value when the vehicle moves forward. When the vehicle retreats, it is usual that a larger braking force than that required when the vehicle moves forward is not required. Therefore, the servo hydraulic pressure Ps is changed between when the vehicle moves forward and when the vehicle moves backward, so that good braking can be performed. You can The operations of the hydraulic pressure control valve 150 and the opening / closing valve 152 are the same as when the vehicle is moving forward, and thus the description thereof is omitted.

As described above, in the present embodiment, the opening / closing valve 152 completely prevents the brake pedal 10 from entering when the vehicle is stopped while the brake pedal 10 is being depressed with a constant stepping force. The sense of incongruity is removed. Further, since the opening / closing valve 152 is provided in the middle of the bypass passage 170 that bypasses the hydraulic pressure control valve 150, even if the opening / closing valve 152 is in the closed state, the hydraulic pressure control valve 150
There is no problem in controlling the hydraulic pressure by.

Further, in the on-off valve 152, the piston 15
8 and the cylinder bore 254 do not have a seal member such as a cup seal or an O-ring, so that the piston 1
The sliding resistance of 58 is small, and the piston 158 can be moved at a time when the master cylinder hydraulic pressure Pm is small.

Further, since the check valve 202 is provided to prevent the supply of the brake fluid to the servo hydraulic pressure generating chamber 48, the brake pedal 10 is further stepped on and the hydraulic pressure control valve 150 is increased when the brake fluid is stopped. Even when the pressure is applied, the brake pedal 10 does not enter, and the driver's discomfort is eliminated.

In addition, the fourth port 166 and the check valve 17
8 allows the brake fluid to be supplied from the reservoir 165 when the hydraulic pressure in the servo hydraulic pressure generation chamber 48 becomes equal to or lower than the atmospheric pressure.
The position of the cyst lever is from D to R while depressing
Servo hydraulic pressure generator 46 when switched to
It is possible to favorably prevent the servo hydraulic pressure from not being generated when the increase and decrease in the pedal effort is repeated without releasing the depression of the brake pedal 10.

Further, since the stroke simulator 56 is provided, it is possible to suppress a sudden increase in the hydraulic pressure in the second hydraulic chamber 194 when the hydraulic pressure control valve 150 shifts from the first state to the second state. . As a result, the caliper hydraulic pressure P
A rapid increase in w can be suppressed and the controllability of braking force can be improved. In particular, since the master cylinder hydraulic pressure set value P ₁ when the hydraulic pressure control valve 150 shifts from the first state to the second state is set low, the hydraulic pressure control valve 150 moves from the first state to the second state. If the caliper hydraulic pressure Pw suddenly increases at the time of shifting to, the deceleration of the vehicle rapidly increases and the riding comfort deteriorates. However, according to the present invention, this inconvenience can be satisfactorily avoided. Further, even when the vehicle shifts to the second state at the time of braking while traveling on a low μ road, the sudden increase in the braking force is small, and the sudden increase in the slip of the wheels can be avoided.

Further, even after the hydraulic pressure control valve 150 has changed from the first state to the second state, an increase in stroke due to an increase in the pedal effort of the brake pedal 10 is allowed, so that the brake feeling is improved and the control is controlled. The sex can be improved.

Further, in the stroke simulator 56, since the set load of the spring 228 is easily adjusted, it is easy to increase the hydraulic pressure of the second hydraulic chamber 194 at the time of transition from the first state to the second state. Can be adjusted to.

Further, the bypass passage 168 and the check valve 1
Since 72 is provided, it is possible to suppress the delay in braking effectiveness at the initial stage of starting the depression operation of the brake pedal 10.

Further, when the caliper 16 is eccentric from the axis L of the rotor 18, the steering knuckle 16
Since it can be rotated about the axis line L of the rotor 18 while being connected to, the inclination of the caliper can be avoided,
The diameter of the rotor 18 can be increased while avoiding the contact of the caliper 16 with the rotor 18 or the wheel disk.

Further, since one servo hydraulic pressure generator 46 can generate servo hydraulic pressure both when the vehicle is moving forward and backward, one servo hydraulic pressure generating device is used before and after the caliper 16 as in the conventional case. The structure of the entire disc brake becomes simpler and the device can be made smaller than the case where the device is provided. The effect of reducing the device cost can also be obtained.

In the on-off valve 152 of the above embodiment, the hydraulic pressure Pm of the master cylinder is supplied to the hydraulic chamber 274, and the piston 158 is moved when the hydraulic pressure Pm of the master cylinder 12 becomes equal to or higher than the set value P _0. However, instead of the master cylinder hydraulic pressure Pm, the caliper hydraulic pressure P
When w is supplied and the caliper hydraulic pressure Pw becomes equal to or greater than the set value, the closed state may be switched.

A check valve 202 is provided between the hydraulic pressure control valve 150 and the servo hydraulic pressure generator 46, and the servo hydraulic pressure generator 46 is passed through the check valve 178 to the reservoir 16
5 is omitted, the bypass passage 170, the opening / closing valve 152 and the check valve 174 are omitted, and the brake pedal 10 is prevented from entering when the vehicle is stopped, the brake pedal 10 is prevented from entering due to the pedal being increased while the vehicle is stopped, and the servo hydraulic chamber. The brake fluid can be replenished to the valve 48.

Further, the control valve 44 is the control valve 4 shown in FIG.
If it is changed to 00, the stroke simulator 56 becomes unnecessary, and the structure of the liquid pressure brake device can be simplified. In the control valve 400, the same members as those of the control valve 44 are designated by the same reference numerals, and the description thereof will be omitted. Only the on-off valve 402 will be described. The on-off valve 402 includes a piston 412, a spring 414, etc., which are fitted in a cylinder bore 410 formed in a housing 404 in a liquid-tight and slidable manner.

Both ends of the cylinder bore 410 have screw holes 416.
And the cylinder bore 418.
Is closed by a plug 424, and an atmospheric pressure chamber 426 formed inside the plug 424 is opened to the atmosphere by a through hole 430. A piston 432 is fitted in the cylinder bore 418 so as to be liquid-tight and slidable. The atmospheric pressure chamber 434 formed by the portion of the cylinder bore 418 communicating with the cylinder bore 410 and the piston 432 is open to the atmosphere by the passage 436, and the hydraulic pressure formed by the portion on the opposite side of the cylinder bore 418 and the piston 432. A liquid passage 272 communicating with the master cylinder 12 is communicated with the chamber 438.

The head 442 of the piston 412 has the atmospheric pressure chamber 4
26, the end portion on the opposite side of the piston 412 projects into the atmospheric pressure chamber 434 and can be engaged with the piston 432 by abutting. A spring 414 is disposed between the head 442 of the piston 412 and the plug 424, and the set load of the spring 414 is determined by the relationship with the pressure receiving area of the piston 432. An annular groove-shaped liquid passage 450 is formed in the middle of the piston 412, and when in the original position shown in the drawing, the bypass passage 17 is formed.
It matches 0 and keeps it open.

In the on-off valve 402 constructed as described above, the hydraulic pressure Pm of the master cylinder is changed to the spring 414.
The piston 412 is held by the spring 414 at a position where the head 442 abuts the bottom surface of the screw hole 416 while the load is small with respect to the set load. In this state,
The piston 432 is at the retracted end position, the liquid passage 450 matches the bypass passage 170, and allows the bypass passage 170 to communicate with each other.

The hydraulic pressure Pm of the master cylinder is the spring 4
When it becomes larger than the set load of 14, the on-off valve 402
Is closed. The piston 432 is moved against the biasing force of the spring 414, and accordingly the piston 4 is moved.
10 is moved to the atmospheric pressure chamber 426 side. as a result,
The liquid passage 450 is disengaged from the bypass passage 170, and the bypass passage 170 is blocked. Therefore, even if the vehicle stops with the brake pedal 10 being depressed, the brake fluid in the hydraulic pressure chambers 41 and 42 of the caliper is prevented from flowing out to the servo hydraulic pressure generating chamber 48, and the braking force becomes insufficient at the time of stop. Is well avoided, and the brake pedal 10
It is possible to eliminate the discomfort of the driver due to the entry of the vehicle.

At the time when the hydraulic pressure control valve 150 shifts from the first state to the second state, the movement of the piston 432 has already started. Therefore, as the hydraulic pressure in the hydraulic chamber 438 increases, The piston 432 and the piston 412 are moved upward in the drawing, and a part of the brake fluid in the master cylinder 12 is stored in the hydraulic chamber 438. As a result, the master cylinder hydraulic pressure Pm and the caliper hydraulic pressure P when the hydraulic pressure control valve 150 shifts from the first state to the second state.
The rapid increase of w is suppressed.

Further, even if the hydraulic pressure control valve 150 shifts to the second state and the communication between the second hydraulic chamber 194 and the first hydraulic chamber 181 is cut off, the pedal effort of the brake pedal 10 increases. Accordingly, the piston 432 and the piston 412 are moved upward in the drawing. Therefore, an increase in stroke is allowed with an increase in the pedal effort of the brake pedal 10, the brake feeling is improved, and the controllability of the braking force can be improved.

The control valve may include the hydraulic control valve 460 and the pilot type on-off valve 462 shown in FIG. The hydraulic control valve 460 includes a housing 464,
Valve piston 466, spring 4 as biasing means
It is equipped with 68 etc. The valve piston 466 is a stepped piston having a large diameter portion and a small diameter portion, and is fitted into the stepped cylinder bore 469 of the housing 464, whereby the first hydraulic pressure chamber 470, the second hydraulic pressure chamber 472, and An atmospheric pressure chamber 474 is formed.

On the other hand, a liquid passage 480 is formed in the valve piston 466 so as to penetrate therethrough in the axial direction.
82 is provided. On the other hand, in the housing 464,
1st port 484, 2nd port 486, 3rd port 48
8 and a through hole 490 are formed, and the third port 4
An opening / closing valve 492 and a check valve 494 are provided in series at 88.

The on-off valve 482 is a check valve having a forward direction from the first hydraulic pressure chamber 470 to the liquid passage 480 with a valve opening projection 496 added thereto.
Is opened at the most retracted end position on the first hydraulic chamber 470 side. The on-off valve 492 is a check valve having a forward direction from the second hydraulic pressure chamber 472 toward the third port 488, and a valve opening protrusion 498 added to the check valve. Open when in the forward end position. The check valve 494 has a direction opposite to that of the on-off valve 492 as a forward direction. A third hydraulic chamber 500 is formed between the open / close valve 492 and the check valve 494.

The master cylinder 50 is attached to the first port 484.
2, caliper 504, second port 486, third port 4
A servo hydraulic pressure generator 506 is connected to 88. In addition, the second hydraulic chamber 472 is bypassed by bypassing the hydraulic control valve 460.
The opening / closing valve 462 is provided in a bypass passage 508 connecting the third hydraulic chamber 500 and the third hydraulic chamber 500. The on-off valve 462 is connected to the master cylinder 502 by the pilot passage 510 and is closed when the master cylinder hydraulic pressure exceeds the set value.

The hydraulic control valve 460 constructed as described above.
Is the same as the hydraulic pressure control valve 150.
First hydraulic chamber 470, second hydraulic chamber 472 accompanying movement of 66
By connecting / disconnecting between the third hydraulic chamber 500 and the third hydraulic chamber 500, the hydraulic pressure of the second hydraulic chamber 472 is higher than the hydraulic pressure of the first hydraulic chamber 470 and is high according to the hydraulic pressure of the first hydraulic chamber 470. However, it is different in that the brake fluid is allowed to pass from the master cylinder 502 side to the servo hydraulic pressure generation device 506 side without the check valve 494.

Therefore, although the supply of the brake fluid to the servo hydraulic pressure generation device 506 is performed without any trouble, if the hydraulic pressure of the servo hydraulic pressure generation device 506 becomes lower than the hydraulic pressure of the caliper 504 or the master cylinder 502, the brake pedal Intrusion occurs. In this embodiment, in order to avoid this, a check valve 494 is provided and the hydraulic pressure control valve 150 is provided.
Similarly, in the state where the hydraulic pressure of the servo hydraulic pressure generator 506 is lower than the hydraulic pressure of the caliper 504 as the brake actuator, the flow of the brake fluid from the latter to the former is not permitted.

In addition, the present invention can be applied not only to the above-mentioned exposed type disc brake but also to a caliper floating type disc brake. In the caliper floating disc brake, the caliper has a cylinder only on one side of the disc rotor, and is supported by a mounting bracket so as to be movable in the axial direction of the rotor. In this case, if the mounting bracket that supports the brake pad is attached to the fixed member via at least two links, the mounting bracket receives the accompanying torque of the caliper and rotates about the rotation center of the disc rotor during braking. It will move.

Furthermore, the position and number of links can be changed as appropriate according to the shape and size of the brake main body.

In each of the above embodiments, the servo hydraulic pressure generator 46 is connected to the link 70, but it may be connected to the caliper 16 or the pin 75.

Further, in each of the above embodiments, when the vehicle moves forward, the drive member 80 is moved in the vehicle forward direction to pull the second piston 102 to generate servo hydraulic pressure, and when the vehicle moves backward, the drive member 80 drives the vehicle. Although the servo hydraulic pressure is generated by moving in the backward direction and pushing the first piston 100, the servo hydraulic pressure generator 46 is arranged so as to be reversed, or the servo cylinder driving member causes the servo hydraulic pressure to be generated. The cylinder may be driven.

The drive member 80 in each of the above embodiments.
Is generally a U-shaped member, but it may be a member having another shape such as an annular shape. What is necessary is just to have a pair of action parts integrally and drive the servo cylinder.

Further, in each of the above embodiments, the hydraulic pressure control valve 150, the opening / closing valve 152, and the check valves 178 and 202 are formed in the same housing 154, but they are formed in separate housings. Good. Further, a mode in which any two or more of these valves are configured in the same housing is also conceivable.

Further, in each of the above embodiments, the master cylinder hydraulic pressure Pm or the servo hydraulic pressure Ps is supplied to both the front and rear wheel brake wheel cylinders via the control valve 44. However, the master cylinder hydraulic pressure Pm may be directly supplied to either one of the wheel cylinders. In that case, the pedaling force of the brake pedal 10 may be maintained even after the control valve 44 has shifted to the second state. Strokes will be increased with increasing.

According to the first invention, the check valve 202,
The reservoir 165, the check valve 178, etc. are not essential. Even if this is not provided, if the driver keeps the pedaling force of the brake pedal 10 constant at the time of stop, it is possible to prevent the brake pedal 10 from entering. Further, according to the second aspect of the invention, the reservoir 165, the check valve 178 and the like are not essential. Even if these are not provided, it is possible to favorably prevent the brake pedal 10 from entering when the vehicle is stopped.

Further, according to the third invention, since the brake fluid can be supplied to the servo hydraulic pressure generating chamber 48, the opening / closing valves 152,
Even if the check valve 202 is not provided, it is possible to reduce the amount of the brake pedal 10 entering.

Besides, the present invention can be implemented in various modified and improved modes based on the knowledge of those skilled in the art.

[Brief description of drawings]

FIG. 1 is a system diagram showing a hydraulic brake device according to an embodiment of the present invention.

FIG. 2 is a front sectional view showing a servo hydraulic pressure generator provided in the hydraulic brake device.

FIG. 3 is a front sectional view showing an operating state of the servo hydraulic pressure generator different from that of FIG.

FIG. 4 is a front cross-sectional view showing an operating state of the servo hydraulic pressure generator, which is different from those in FIGS. 1 and 2.

FIG. 5 is a front view showing the servo hydraulic pressure generator with a driving member in section.

FIG. 6 is a VV sectional view of the servo hydraulic pressure generator.

FIG. 7 is a front sectional view showing the disc brake.

FIG. 8 is a plan view showing the disc brake.

FIG. 9 is an AA showing a hydraulic pressure control valve of the hydraulic brake device.
FIG.

FIG. 10 is a BB sectional view of the hydraulic control valve.

FIG. 11 is a CC cross-sectional view of the fluid pressure control valve.

FIG. 12 is a front sectional view of a stroke simulator provided in the hydraulic brake device.

FIG. 13 is an explanatory view showing the states before and after the rotation of the caliper in the disc brake in comparison.

FIG. 14 is a front sectional view conceptually showing the hydraulic pressure control valve.

FIG. 15 is a front sectional view conceptually showing an operating state of the hydraulic control valve, which is different from that in FIG.

FIG. 16 is a front sectional view conceptually showing an operating state of the hydraulic control valve, which is different from those in FIGS. 14 and 15.

FIG. 17 is a graph showing the relationship among the master cylinder hydraulic pressure, the caliper hydraulic pressure, and the servo hydraulic pressure in the brake device.

FIG. 18 is a graph showing the relationship between the master cylinder hydraulic pressure and the pedal effort in the brake device.

FIG. 19 is a graph showing a relationship between caliper hydraulic pressure and pedaling force in the brake device.

FIG. 20 is a graph showing the relationship between the stroke and the pedal effort in the brake device.

FIG. 21 is a part of a front sectional view of a hydraulic pressure control valve in a hydraulic brake device according to another embodiment of the present invention.

FIG. 22 is a system diagram showing a hydraulic braking device that is another embodiment of the present invention.

[Explanation of symbols]

 12 master cylinder 16,17 caliper 24,26 cylinder 41,42 hydraulic chamber 44,400 control valve 46 servo hydraulic pressure generator 150 hydraulic control valve 152,402 on-off valve 165 reservoir 168 bypass passage 170 bypass passage 176 liquid passage 178 Check valve 196 Third hydraulic chamber 200 Liquid passage 202 Check valve 288,450 Liquid passage

Claims (3)

[Claims] 1. A brake-operation-compatible hydraulic pressure generator that generates hydraulic pressure according to the operation of a brake operating member, a pad support member that supports the brake pad, and a brake cylinder that presses the brake pad against the disc rotor by supplying the hydraulic pressure. A brake actuating device that is attached to a fixed member near the disc rotor so as to be rotatable in the rotational direction of the disc rotor; and a servo hydraulic pressure generation device that generates servo hydraulic pressure based on the rotation of the pad support member. A first hydraulic chamber connected to the brake operation-compatible hydraulic pressure generating device, a second hydraulic pressure chamber connected to the brake operating device, and a third hydraulic pressure chamber connected to the servo hydraulic pressure generating device. And by connecting and disconnecting the first hydraulic chamber, the second hydraulic chamber and the third hydraulic chamber, the hydraulic pressure of the second hydraulic chamber is equal to or higher than the hydraulic pressure of the first hydraulic chamber, In a hydraulic brake device comprising a hydraulic control valve for controlling a height according to the hydraulic pressure of the first hydraulic chamber, the hydraulic pressure control valve is a servo hydraulic pressure generator hydraulic pressure of the brake operating device. In the state lower than hydraulic pressure, the flow of brake fluid from the latter to the former is not allowed, and a bypass passage connecting the brake actuator and the servo hydraulic pressure generator by bypassing the hydraulic pressure control valve is provided,
An on-off valve that opens in the middle of the bypass passage when the hydraulic pressure of one of the brake operation-compatible hydraulic pressure generating device and the brake operating device is lower than a set value, and closes when the hydraulic pressure is higher than the set value. A hydraulic brake device characterized by being provided. 2. The hydraulic fluid is allowed to flow from the servo hydraulic pressure generating device to the third hydraulic pressure chamber in the middle of the hydraulic passage connecting the servo hydraulic pressure generating device and the third hydraulic pressure chamber, but is reversed. 2. The hydraulic brake device according to claim 1, further comprising a check valve for blocking the directional flow. 3. A brake operation-compatible hydraulic pressure generator that generates hydraulic pressure in accordance with the operation of a brake operating member, a pad support member that supports the brake pad, and a brake cylinder that presses the brake pad against the disc rotor by supplying the hydraulic pressure. A brake actuating device that is attached to a fixed member near the disc rotor so as to be rotatable in the rotational direction of the disc rotor; and a servo hydraulic pressure generation device that generates servo hydraulic pressure based on the rotation of the pad support member. A first hydraulic chamber connected to the brake operation-compatible hydraulic pressure generating device, a second hydraulic pressure chamber connected to the brake operating device, and a third hydraulic pressure chamber connected to the servo hydraulic pressure generating device. And by connecting and disconnecting the first hydraulic chamber, the second hydraulic chamber and the third hydraulic chamber, the hydraulic pressure of the second hydraulic chamber is equal to or higher than the hydraulic pressure of the first hydraulic chamber, A hydraulic brake device comprising a hydraulic control valve for controlling a height according to the hydraulic pressure of a first hydraulic chamber, wherein the hydraulic brake device is provided with a reservoir, and the reservoir and the servo hydraulic pressure are generated. The device is connected to the device by a liquid passage, and a check valve is provided in the middle of the liquid passage to allow the flow of the hydraulic fluid from the reservoir to the servo hydraulic pressure generator, but to prevent the flow in the reverse direction. Hydraulic brake device.