JPH08301087A - Caliper inside incorporated type antilock control device - Google Patents

Abstract

PURPOSE: To provide an antilock control device which can increase and reduce brake fluid pressure by adjusting fluid pressure chamber capacity of a wheel cylinder by controlling this pressure adjusting piston, by arranging the pressure adjusting piston in the wheel cylinder formed in a brake caliper. CONSTITUTION: When a wheel is locked at traveling time, a motor 22 is driven, and a cam 14 rotates in the counter clockwise direction through a pinion, and a roller moves by an action of a cam surface, and a swing arm swings, and a push rod 9 also moves rightward. As a result, a pressure adjusting piston 8 moves rightward by fluid pressure in a fluid pressure chamber 7a, and an outer peripheral groove 8a on the pressure adjusting piston and an inner peripheral groove 3a on an caliper inner peripheral surface are put in a nonsuperposed condition, and a valve mechanism is closed, and capacity of the fluid pressure chamber 7a is expanded, and brake fluid pressure is reduced, and brake force is weakened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-lock control device suitable for controlling a wheel lock that occurs when a sudden brake (during rapid pressurization) is applied to a vehicle brake or the like. The present invention relates to a compact and lightweight antilock control device in which an antilock control device is incorporated in a caliper of a disc brake.

[0002]

2. Description of the Related Art In recent years, an anti-lock control device has been actively developed for the purpose of improving steering stability during braking and facilitating a driver's driving operation. As an anti-lock control device for this type of vehicle, JP-A-64-4
Those disclosed in Japanese Patent No. 7650 or Japanese Patent Publication No. 6-30582 are known.

In the antilock control device described in the former publication, an antilock control modulator is arranged in the middle of a pipe connecting a master cylinder and a wheel cylinder, and a step valve is used as a ball valve in the modulator. Then, it is precisely controlled to eliminate the wheel lock phenomenon.

However, in the above antilock control device, in addition to the brake device mounted on the wheel side, a modulator for executing antilock control needs to be provided in the middle of the brake pipe, and the device is large. There is a problem that it will become. Separately, in order to reduce the size of the anti-lock control device, a brake caliper in which a modulator is incorporated has been proposed (Japanese Patent Laid-Open No. 61-166759). This antilock control device incorporates a piezoelectric brake control mechanism in a brake caliper, and performs brake control by utilizing deformation of a piezoelectric element. However, this device also requires a displacement member in order to increase the amount of movement of the brake piston, which complicates the configuration and increases the manufacturing cost. Furthermore, the caliper located under the spring of the vehicle body has a large weight and size. However, there is a problem that it is difficult to incorporate a complicated mechanism in that there is a limitation in the above.

[0005]

SUMMARY OF THE INVENTION Therefore, according to the present invention, a valve mechanism for arranging a pressure adjusting piston in a wheel cylinder formed in a brake caliper and for opening and closing a flow path between a hydraulic chamber and a master cylinder by moving the pressure adjusting piston. By controlling the pressure adjusting piston using a drive mechanism such as a cam mechanism, the opening and closing of the valve mechanism is controlled and the volume of the hydraulic chamber of the wheel cylinder is adjusted to increase or decrease the brake hydraulic pressure. It is an object of the present invention to propose a new antilock control device that can be used and solve the above problems.

[0006]

For this reason, the anti-lock control device incorporated in the caliper of the present invention has a wheel cylinder 7 formed in the caliper 3 of the brake device and a slidable body arranged in the wheel cylinder 7. Piston 6
A hydraulic pressure chamber 7a defined in the wheel cylinder 7 by the piston, a pressure adjusting piston 8 that can be retracted in the hydraulic pressure chamber 7a to change the volume of the hydraulic pressure chamber 7a, and the hydraulic pressure chamber 7a. A flow passage 20 that communicates with a master cylinder, a valve mechanism that opens and closes the flow passage 20 as the pressure adjusting piston 8 moves, a control mechanism that controls the amount of movement of the pressure adjusting piston 8, and the control mechanism. Electronic control unit (EC
U) and are provided, which is a means for solving the problem.

[0007]

[Action]

[During normal braking] When the brake pedal 1 is depressed and hydraulic pressure is generated in the master cylinder 2, this hydraulic pressure is passed through the flow path 20 →
The fluid is supplied to the hydraulic chamber 7a through the flow path 3b → the inner peripheral groove 3a of the caliper → the outer peripheral groove 8a of the pressure adjusting piston 8 → the flow path 8b, and the piston 6 is pressed to perform the braking action. When the depression of the brake pedal is released, the hydraulic pressure in the hydraulic chamber 7a is returned to the master cylinder in the route opposite to the above, and the brake is released.

[During Antilock Control] When the wheels are locked during traveling, the motor 22 is driven and the groove cam 14 is rotated counterclockwise via the pinion 18. The rotation of the groove cam 14 causes the roller surface 13 to move due to the action of the cam surface 17, which causes the swing arm to swing and further the push rod 9 to move to the right. As a result, the pressure adjusting piston 8 moves to the right by the hydraulic pressure in the hydraulic pressure chamber 7a, and the outer peripheral groove 8a of the pressure adjusting piston and the inner peripheral groove 3a of the caliper inner peripheral surface are brought into a non-overlapping state to open the valve mechanism. At the same time, the volume of the hydraulic chamber 7a is expanded, the brake hydraulic pressure is reduced, the braking force is weakened, and the locked state of the wheels is released. At the time of re-pressurization, the motor 22 is rotated in the reverse direction, the pressure adjusting piston is pushed back into the hydraulic chamber 7a while moving the swing arm in the initial position direction, and re-pressurization is executed. Further, when a command for holding the brake fluid pressure is issued, the motor 22 stops and holds the brake fluid pressure in the fluid pressure chamber 7a.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1 is a partial cross-sectional view of an anti-lock control device according to an embodiment of the present invention, FIG. 2 is a partial cross-sectional view in the direction of arrow A in FIG. 1, and FIG. 3 is a view in the direction of arrow B of FIG. is there. 1 to 3, 1 is a brake pedal, 2 is a master cylinder, 3 is a caliper in a brake device, 4 is a disc pad, 5 is a disc, and 6 is a piston for holding a disc pad 4 on one side. Is assembled. A wheel cylinder 7 is formed in the caliper 3, and a piston 6 is slidably arranged in the wheel cylinder 7. The piston 6 defines a hydraulic chamber 7a in a wheel cylinder 7, and a pressure adjusting piston 8 is slidably provided in the hydraulic chamber 7a.

The pressure-adjusting piston 8 described above has a flow passage 8b communicating with the hydraulic chamber 7a therein and an outer peripheral groove 8a communicating with the flow passage 8b formed on the outer peripheral surface thereof. On the other hand, an inner peripheral groove 3a is formed on the inner peripheral surface of the caliper side that slidably holds the pressure adjusting piston 8, and a flow path 3b communicating with the inner peripheral groove 3a is formed in the caliper body. There is. The flow passage 3b communicates with the master cylinder 2 via the flow passage 20, and the flow passage 20 is formed of a pipe having a diameter larger than that of a normal flow passage in order to reduce the waste stroke of the pressure adjusting piston 8 as much as possible. Has been done. The outer peripheral groove 8a of the pressure adjusting piston 8 and the inner peripheral groove 3a of the caliper 3 constitute a spool type valve mechanism. That is, as shown in FIG. 1, this valve mechanism has the hydraulic chamber 7 when the outer peripheral groove 8a of the pressure adjusting piston and the inner peripheral groove 3a of the caliper inner peripheral surface overlap each other.
a communicates with the master cylinder 2, and when the anti-lock control is executed in a manner described later and the pressure adjusting piston 8 moves, the inner peripheral groove 3a and the outer peripheral groove 8a become non-overlapping, and the hydraulic chamber 7a and the master cylinder 7a. It has a function of disconnecting communication with the cylinder 2. The outer peripheral groove 8a of the pressure adjusting piston 8 and the inner peripheral groove 3a of the caliper 3 are formed with an inclined surface at either one or both corners, whereby the outer peripheral groove 8a and the inner peripheral groove 3a are gradually overlapped. It is also possible to reduce noise and the like generated when the flow path is closed.

A push rod 9 is in contact with an end portion of the pressure adjusting piston 8. The push rod 9 is connected to a swing arm 10 by a pin 11. Further, the swing arm 10 has a shaft 12 at one end thereof. Three
A roller 13 is rotatably supported on one side and a roller 13 is rotatably provided on the other end as shown in FIG. Roller 13 is shaft 1
It is fitted in a groove 15 (see FIG. 3) formed in a groove cam 14 rotatably attached to the caliper 3 by 6. The inner peripheral edge of the groove 15 forms a cam surface 17 having a function of moving the roller 13 in the horizontal direction in FIG. Further, the outer periphery of the groove cam 14 is formed as a gear, and a pinion 18 is engaged with this gear, and the pinion 18 is attached to the output shaft of the motor 22 (note that the amount of movement of the pressure adjusting piston is the same). And the control mechanism of the pressure regulating piston). Therefore, when the groove cam 14 rotates counterclockwise around the shaft 16 from the state of FIG. 2, the action of the cam surface 17 (swing arm swinging means).
As a result, the roller 13 moves horizontally to the right in FIG. 2, whereby the pressure adjusting piston 8 shown in FIG. 1 moves to the right in FIG. 1 due to the hydraulic pressure in the hydraulic chamber 7a. It will be.

The motor 22 is an electronic control unit (EC
U), the electronic control unit 20 rotationally drives the motor 22 based on a signal from the speed sensor 23, and executes antilock control in a manner described later. In the figure, 24 is a dust seal between the piston 6 and the cylinder, and 25 is a seal member.

The operation of the antilock control device according to the above configuration will be described. [Normal Braking] During normal braking, the motor 22 does not operate because there is no command from the electronic control unit, the groove cam 14 takes the initial position shown in FIG.
3, the swing arm 10 and the pressure adjusting piston 8 also do not operate, so that the state shown in FIG. 1 is maintained as a whole.
Therefore, in this state, the outer peripheral groove 8a of the pressure regulating piston and the inner peripheral groove 3a of the caliper inner peripheral surface are overlapped with each other so that the valve mechanism is opened (see the enlarged view of FIG. 4). Is the flow path 8b → the outer peripheral groove 8a → the inner peripheral groove 3a of the caliper
→ Communication with the master cylinder 2 through the flow path 3b → the flow path 20. Therefore, when the brake pedal 1 is stepped on and hydraulic pressure is generated in the master cylinder 2, this hydraulic pressure is supplied to the hydraulic chamber 7a via the above-mentioned path and pushes the piston 6 to the left in the drawing to execute the braking action. To do. When the depression of the brake pedal is released, the hydraulic pressure in the hydraulic chamber 7a is returned to the master cylinder in the route opposite to the above, and the brake is released.

[During Antilock Control] When the brake pedal 1 is depressed to brake the vehicle, hydraulic pressure is generated in the master cylinder 2. As described above, this hydraulic pressure is supplied to the hydraulic chamber 7a in the wheel cylinder to apply a braking force to the wheels. By the way, in this state, the state of the wheel is always detected by a sensor (for example, a speed sensor) 23 for detecting the skid state of the wheel, and the detection signal is input to a known electronic control unit, which the electronic control unit inputs. The wheel speed, slip ratio, deceleration, etc. are calculated based on the above. Then, the skid state of the wheels is evaluated based on this calculation result, and the motor 22 is controlled as follows to reduce the brake fluid pressure,
Various modes such as holding and repressurizing are executed.

That is, when the wheels are locked during traveling and the brake release signal is output from the electronic control unit (ECU), the motor 22 is driven and the groove cam 14 is moved counterclockwise in FIG. 2 via the pinion 18. Rotate to. The rotation of the groove cam 14 causes the roller surface 13 to move to the right in FIG. 2 by the action of the cam surface 17, which causes the swing arm to swing to the right in FIG. 1 about the shaft 12 and the push rod 9 to the right. Move towards. As a result, the pressure adjusting piston 8 moves to the right due to the hydraulic pressure in the hydraulic chamber 7a. As the pressure adjusting piston 8 moves, as shown in the enlarged view of FIG.
a and the inner peripheral groove 3a on the inner peripheral surface of the caliper are in a non-overlapping state to open the valve mechanism, and at the same time, the volume of the hydraulic chamber 7a is expanded to reduce the brake hydraulic pressure, weaken the braking force, and reduce the wheel force. The locked state is released.

Further, at the time of repressurization, the motor 22 is rotated in the reverse direction, the swing arm is moved toward the initial position, and the pressure adjusting piston is pushed back into the hydraulic chamber 7a to perform repressurization. Also, when a command to hold the brake fluid pressure is issued,
The motor 22 stops and holds the brake fluid pressure in the fluid pressure chamber 7a. As described above, according to the present embodiment, the pressure in the hydraulic chamber 7a is controlled by the operation of the pressure adjusting piston 8, whereby the brake hydraulic pressure is reduced, held, and repressurized.

Further, the hydraulic pressure control (pressure reduction, holding, repressurization) of the brake device is performed independently or for each wheel of each channel according to the state of each wheel. The antilock control is released when the signal from the electronic control unit disappears. That is, when the signal from the electronic control unit disappears, the groove cam 14 is returned to the initial position by the motor 22, and the pressure adjusting piston is also returned to the initial position to be in the state shown in FIG. 1 and the normal braking state. Since the spool type valve mechanism is used, the valve mechanism is closed by a slight stroke of the pressure adjusting piston, and the response is good.

In the above embodiment, a groove cam is used as the cam mechanism as the swing arm swinging means.
As shown in (a), various types of cam mechanisms such as a cam that moves vertically by driving a motor can be adopted, and a swing mechanism can be used by using a link mechanism as shown in FIG. 4 (b). The arm can also be swung.

Next, a second embodiment of the present invention will be described with reference to FIGS. The second embodiment is different in that a poppet valve mechanism is adopted in place of the spool type valve mechanism of the first embodiment, and the other configurations are the same as those of the first embodiment. In FIGS. 6 and 7, a poppet valve 3c, which is biased toward the valve seat 3e by a spring 3d, is arranged in the flow path 3b formed in the caliper 3. A rod 3f is attached to the poppet valve 3c.
During non-antilock control, as shown in FIG. 6, it comes into contact with the outer peripheral surface of the pressure regulating piston to push up the poppet valve upward in the figure to open the flow path 3b. On the other hand, a guide groove 8a 'is formed on the outer circumference of the pressure adjusting piston 8, and when the pressure adjusting piston 8 moves to the right in FIG. 6, the rod 3f of the poppet valve falls into the guide groove 8a' to form the flow passage 3b. It acts to close. The end portion of the guide groove 8a is formed as an inclined surface 8c, which smoothly blocks the flow path by the poppet valve and prevents noise and the like due to water hammer. The guide groove 8a 'communicates with the hydraulic chamber 7a via the flow path 8b as in the first embodiment. That is, as shown in FIG. 6, this poppet valve opens the flow passage 3a when the rod c is pushed upward by the outer circumference of the pressure adjusting piston against the urging force of the spring 3d.
When the pressure adjusting piston 8 moves to the right in FIG. 6 and enters the state of FIG. 7, the rod 3f of the poppet valve falls into the guide groove 8a 'to close the flow passage 3b.

The operation of the antilock control device according to the above configuration will be described. [Normal Braking] During normal braking, the motor 22 does not operate because there is no command from the electronic control unit, the groove cam 14 takes the initial position shown in FIG.
3, the swing arm 10 and the pressure adjusting piston 8 also do not operate, so that the state shown in FIG. 1 is maintained. Therefore, in this state, as shown in the enlarged view of FIG. 6, the poppet valve is pushed upward by the outer circumference of the pressure adjusting piston against the urging force of the spring 3d, and the flow path 3
a is open. As a result, the hydraulic chamber 7a communicates with the master cylinder 2 through the flow passage 8b, the guide groove 8a ', the open poppet valve 3c, the flow passage 3b, and the flow passage 20, and the brake pedal 1 is depressed to depress the master cylinder. When a hydraulic pressure is generated in 2, the hydraulic pressure is supplied to the hydraulic chamber 7a via the above-mentioned path to press the piston 6 leftward in the figure to execute the braking action. When the depression of the brake pedal is released, the hydraulic pressure in the hydraulic chamber 7a is returned to the master cylinder in the route opposite to the above, and the brake is released.

[During Antilock Control] When the wheels are locked during traveling and a brake release signal is output from the electronic control unit (ECU), the motor 22 is driven and the pinion 1
The groove cam 14 is rotated in the counterclockwise direction via 8. The rotation of the grooved cam 14 causes the roller surface 13 to move to the right in FIG. 3 by the action of the cam surface 17, which causes the swing arm to move.
2 and swings to the right in FIG. 1 and push rod 9
Also moves to the right. As a result, the pressure adjusting piston 8 moves to the right due to the hydraulic pressure in the hydraulic chamber 7a. Pressure adjusting piston 8
6, the rod 3f of the poppet valve falls into the guide groove 8a ', the poppet valve closes the flow path 3b, the volume of the hydraulic chamber 7a is expanded, and the brake hydraulic pressure is reduced. The braking force is weakened and the locked state of the wheels is released.

Further, at the time of re-pressurization, the motor 22 is reversely rotated, the swing arm is moved toward the initial position, and the pressure-adjusting piston is pushed back into the hydraulic chamber 7a to perform re-pressurization. Also, when a command to hold the brake fluid pressure is issued,
The motor 22 stops and holds the brake fluid pressure in the fluid pressure chamber 7a. As described above, according to the present embodiment, the pressure in the hydraulic chamber 7a is controlled by the operation of the pressure adjusting piston 8, whereby the brake hydraulic pressure is reduced, held, and repressurized. Further, when the poppet valve is adopted as the valve mechanism, the stroke of the pressure adjusting piston can be shortened.

[0023]

As described above in detail, according to the present invention, the pressure adjusting piston is arranged in the wheel cylinder formed in the brake caliper, and by controlling the pressure adjusting piston, the volume in the wheel cylinder is controlled and the brake is applied. Since the anti-lock control is executed by increasing / decreasing the liquid pressure, the mechanism incorporated in the caliper is simplified, and the anti-lock control device can be manufactured extremely small and inexpensive. Further, when a disk-shaped cam is used for the mechanism for swinging the swing arm, the rotational inertia can be reduced and the antilock control accuracy can be improved. Furthermore, since the valve mechanism is formed by the pressure-adjusting piston and the caliper, or the valve mechanism consisting of the poppet valve is arranged in the caliper, the solenoid valve for closing the flow path from the master cylinder is not required and the configuration is simplified. To be done. Further, since the solenoid valve is not required, the inner diameter of the flow passage that connects the master cylinder and the internal flow passage of the caliper can be increased, thereby eliminating the unnecessary stroke of the pressure adjusting piston. Further, since the caliper 3 that constitutes the brake device is located under the spring of the suspension of the vehicle, it is desirable that the antilock control device incorporated in the caliper 3 be as small as possible. However, the antilock control device according to the present invention has such a demand. It is also possible to deal with. It is possible to achieve excellent operational effects such as.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of an anti-lock control device as a first embodiment according to the present invention.

FIG. 2 is a sectional view taken along arrow A in FIG.

3 is a view on arrow B in FIG. 1. FIG.

FIG. 4 is an enlarged view of the valve mechanism in FIG. 1, showing a non-antilock control state.

FIG. 5 is an enlarged view of the valve mechanism in FIG. 1, showing an antilock control state.

FIG. 6 is an enlarged view of a valve mechanism as a second embodiment, showing a non-antilock control state.

FIG. 7 is an enlarged view of a valve mechanism as a second embodiment, showing an antilock control state.

[Explanation of symbols]

 1 Brake Pedal 2 Master Cylinder 3 Caliper 3a Inner Circumferential Groove 3b Flow Path 4 Disc Pad 5 Disc 7 Wheel Cylinder 7a Hydraulic Chamber 8 Pressure Adjusting Piston 8a Outer Groove 8b Flow Path 9 Push Rod 10 Swing Arm 12 Shaft 13 Roller 14 Groove Cam 15 cam groove 17 cam surface 20 electronic control device 22 motor

Claims (6)

[Claims] 1. A wheel cylinder 7 formed in a caliper 3 of a brake device, a slidable piston 6 arranged in the wheel cylinder 7, and a hydraulic chamber defined in the wheel cylinder 7 by the piston. 7a, a pressure-adjusting piston 8 that can project and retract in the hydraulic chamber 7a to change the volume of the hydraulic chamber, and a flow path 20 that connects the hydraulic chamber 7a and the master cylinder.
A valve mechanism that opens and closes the flow path 20 in accordance with the movement of the pressure adjusting piston 8, a control mechanism that controls the amount of movement of the pressure adjusting piston 8, and an electronic control unit (ECU) that controls the control mechanism. A built-in type anti-lock control device in a caliper, characterized by being equipped with. 2. The valve mechanism includes a groove formed on the outer circumference of a pressure regulating piston, a flow passage formed in the piston for communicating the groove with the hydraulic chamber, and a groove formed on the inner peripheral surface of the wheel cylinder. A master cylinder when the groove formed in the pressure regulating piston and the groove formed in the inner peripheral surface of the wheel cylinder are in a non-overlapping state due to the movement of the pressure regulating piston. The built-in type anti-lock control device in a caliper according to claim 1, wherein communication with the hydraulic chamber is cut off. 3. The valve mechanism includes a poppet valve arranged in a flow passage formed in a caliper that communicates a wheel cylinder and a master cylinder, and the poppet valve forms a flow passage by movement of a pressure adjusting piston. The built-in anti-lock control device in a caliper according to claim 1, wherein the anti-lock control device is configured to operate so as to close. 4. The valve mechanism includes a poppet valve disposed in a flow passage formed in a caliper that communicates a wheel cylinder and a master cylinder, the poppet valve being configured to move a pressure adjusting piston to adjust the pressure adjusting piston. 4. The built-in type anti-lock control device in a caliper according to claim 3, wherein the flow path is closed by being fitted into a recess formed in. 5. The control mechanism of the pressure-adjusting piston swings a swing arm 10 provided on a caliper, a push rod 9 for transmitting the movement of the swing arm to the pressure-adjusting piston 8, and a swing arm. The anti-lock control device incorporated in the caliper according to any one of claims 1 to 4, further comprising: 6. The caliper built-in type anti-lock control device according to claim 5, wherein the means for swinging the swing arm is a cam mechanism.