JPH09323631A - Hydraulic control device and brake device using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To precisely increase and decrease hydraulic pressure, and reduce the weight and size of a device by providing a gear case within the hydraulic chamber of a device body, driving a pressure regulating piston by its gear shaft, and controlling the hydraulic pressure by a solenoid valve through an electronic control device. SOLUTION: A hydraulic chamber 12 is provided within a cylinder 11 formed within a body 10, and allowed to communicate with a hydraulic generating source 1 through a solenoid valve 2 provided within a passage 30 and also with an actuator through a passage 31. A gear case 13 is provided within the hydraulic chamber 12, the rack 20a of a pressure regulating piston 20 is fitted to a gear 22 provided on its gear shaft 15 to provide the stroke of the pressure regulating piston 20. A potentiometer 40 is fixed to a large gear 23 on the end part of the gear shaft 15 to detect the rotating angle of the gear shaft. In a hydraulic control, an electronic control device 7 drives a motor 6 according to the signal of a hydraulic sensor 41 or the like to close the solenoid valve 2. The gear shaft 15 and the gear 22 are then also rotated, and the pressure regulating piston 20 is driven through the rack 20a thereby to reduce the pressure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic pressure control device capable of smoothly increasing and decreasing the hydraulic pressure in a hydraulic pressure control circuit, and further to the hydraulic pressure control device in a caliper of a vehicle disc brake. Built-in, anti-lock,
The present invention relates to a compact and lightweight brake device that can perform smooth hydraulic pressure control such as traction control.

[0002]

2. Description of the Related Art In recent years, the development of an antilock control device for the purpose of improving driving stability during braking and facilitating a driver's driving operation has been actively promoted. Japanese Patent Application Laid-Open No. Sho 64-4 discloses this type of vehicle antilock control device.
The one described in Japanese Patent No. 7650 is known.

[0003] The anti-lock control device described in the above-mentioned publication includes a brake device which is operated by hydraulic pressure supplied from a master cylinder, an anti-lock control modulator arranged in a pipe connecting the master cylinder and the wheel cylinder, and The ball valve in the modulator is precisely controlled by using a step motor, and the hydraulic pressure supplied to the brake device is increased and decreased to eliminate the wheel locking phenomenon.

However, in the above-described anti-lock control device, a modulator for performing anti-lock control must be provided in the middle of the brake pipe, separately from the brake device mounted on the wheel side. There is a problem that it becomes complicated and complicated.

In order to reduce the size of the antilock control device separately from the above-mentioned conventional example, a brake caliper incorporating a brake fluid pressure control mechanism has been proposed (Japanese Patent Laid-Open No. 61-166759). ). This anti-lock control device incorporates a piezoelectric brake fluid pressure control mechanism in a brake caliper and performs brake fluid pressure control by utilizing deformation of a piezoelectric element. However, this device also requires the provision of a displacement member in order to increase the amount of movement of the brake piston provided in the hydraulic control mechanism, which complicates the configuration and increases the manufacturing cost. It is difficult to incorporate a complicated mechanism into the located calipers in terms of weight and size restrictions. Further, since a complicated mechanism is adopted, there is a problem that sound and vibration are easily generated, and the fluid pressure control cannot be smoothly performed.

[0006]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention utilizes a pressure adjusting piston that is moved by a gear to easily and smoothly increase and decrease the hydraulic pressure in a hydraulic circuit. An object of the present invention is to provide a small-sized and lightweight hydraulic control device that can be executed, and a lightweight and small-sized brake device that incorporates the hydraulic pressure control device in a caliper of a disc brake. According to this device, the increase / decrease of the hydraulic pressure in the hydraulic circuit can be smoothly and accurately executed by the gear mechanism, and by incorporating this device in the brake caliper, a lightweight, compact, and low-cost brake device can be obtained. And even anti-lock control of the vehicle,
Fluid pressure control such as traction control and automatic braking can be executed smoothly. In particular, since the amount of movement of the pressure adjusting piston that adjusts the hydraulic pressure in the hydraulic pressure chamber can be controlled using the gear, torque transmission does not fluctuate, and accurate control of the pressure adjusting piston is possible.

[0007]

For this reason, the technical solution adopted by the present invention is arranged in a hydraulic circuit between a hydraulic pressure generation source and an actuator, and controls the hydraulic pressure acting on the actuator. A pressure control device comprising: a cylinder formed in the body of the fluid pressure control device; a fluid pressure chamber formed in the cylinder and communicating with the fluid pressure generation source and an actuator; A gear case arranged, a gear shaft arranged in the gear case, a motor rotating the gear shaft, a pressure adjusting piston that appears and disappears in the hydraulic chamber by the rotation of the gear shaft, and the hydraulic pressure. An electronic control device (EC) for controlling a solenoid valve arranged in a flow path that communicates a room with a hydraulic pressure generation source and the solenoid valve and the motor.
U) and a fluid pressure control device,

A cylinder formed in a caliper of the brake device, a slidable brake piston arranged in the cylinder, a hydraulic chamber defined by the piston in the cylinder, and a hydraulic chamber arranged in the hydraulic chamber. A gear case, a gear shaft arranged in the gear case, a motor that rotates the gear shaft, a pressure adjusting piston that appears and disappears in the hydraulic chamber due to the rotation of the gear shaft, and the hydraulic chamber. An electronic control device (EC) for controlling the electromagnetic valve arranged in a flow path communicating with the hydraulic pressure source and the electromagnetic valve and the motor.
U) is provided.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of a hydraulic control device according to the present invention, and FIG. 2 is a sectional view taken along the line AA in FIG. In FIG. 1, 1 is a hydraulic pressure generation source, 2 is an electromagnetic valve, 3 is a hydraulic pressure control device, 6 is a motor for driving the hydraulic pressure control device, and 7 is an electronic control device (E
CU), 30, 31 are flow channels, 40 is a potentiometer,
Reference numeral 41 denotes a hydraulic pressure sensor, which constitutes a hydraulic pressure control system.

A cylinder 11 is formed in the main body 10 of the hydraulic control device 3, and a hydraulic chamber 12 is formed in the cylinder 11. This hydraulic pressure chamber 12 is a hydraulic pressure generation source (for example, a master cylinder) via an electromagnetic valve 2 provided in the flow path 30.
And to an actuator (for example, a wheel cylinder in a conventional brake device) via a flow path 31.

A gear case 13 is arranged in the hydraulic chamber 12, and the gear case 13 is fixed to the main body 10 in a liquid-tight state by a fixing means such as a nut, and further in the center of the gear case 13. Is an elongated hole 1 in which the gear shaft 15 is arranged.
6 are formed. A piston accommodating window 17 is formed in communication with the elongated hole 16, and a pair of pressure adjusting pistons 20 are smoothly slidably arranged in the piston accommodating window 17.

In the central long hole 16 of the gear case 13,
The gear shaft 15 is supported by bearings 18 and 19. A gear 22 is formed on the gear shaft 15 so as to correspond to the piston housing window 17 of the gear case 13. The gear 20 is fitted with a rack 20a formed on the pressure adjusting piston 20 as shown in FIG. The rack 20a is formed in a portion extending from the pressure adjusting piston 20 as shown in the drawing, and each rack 20a formed in the pair of pressure adjusting pistons 20 meshes with the gear 22. Therefore, when the gear 22 rotates, the rack 2 that meshes with this gear 2
0a moves up and down in the figure with the rotation, and the stroke of the pressure regulating piston 20 is obtained.

In the state shown in FIG. 2, the head portion of the pressure-adjusting piston 20 is held at an initial position which substantially coincides with the outer peripheral surface of the gear case 13, and from this state, the gear 22 is adjusted counterclockwise in the figure. Since the pressure piston 20 is submerged in the gear case 13, the pressure inside the hydraulic chamber 12 can be reduced.
Further, when rotating clockwise, the pressure adjusting piston 20 can protrude from the gear case 13 to pressurize the hydraulic chamber 12.

A large gear 23 is fixed to the end of the gear shaft 15, and the large gear 23 meshes with a pinion 24 attached to the output shaft of the motor 6 to form a gear drive mechanism. . Further, a potentiometer 40 is fixed to the large gear 23, and the potentiometer 40 can detect the rotation angle (positional information) of the gear shaft. Further, a flexible boot 25 is put around the gear case 13, and the boot 25
Is fixed to the gear case 13 in a liquid-tight manner by a fixing means 25a such as a band, and the boot 25 prevents the liquid in the hydraulic chamber 12 from leaking out from the piston housing window 17.

Therefore, when the gear shaft 15 rotates counterclockwise from the position shown in FIG. 2, the pressure adjusting piston 20 is sunk into the piston housing window 17 formed in the gear case 13, whereby the hydraulic pressure is increased. The volume in the chamber 12 can be increased. At this time, the boot 25 is also deformed by the hydraulic pressure in the hydraulic chamber 12 as the pressure adjusting piston 20 moves. If a liquid-tight seal having slidability is provided between the piston housing window 17 and the pressure adjusting piston 20, the boot can be omitted.

Although the above-described example in which one gear 22 is provided on the gear shaft 15 has been described, a plurality of gears are formed on the gear shaft 15, and a piston housing window and a pressure adjusting piston are provided corresponding to the gears. It is also possible to arrange them. Further, in the above-described embodiment, the case where one pair of pressure adjusting pistons 20 are provided for one gear has been described as an example, but the number of pressure adjusting pistons may be one, and if necessary, they may be different from each other. By adopting an arrangement in which the racks do not interfere with each other, it is possible to arrange three or more pressure adjusting pistons for one gear. When the number of pressure adjusting pistons is increased in this way, the hydraulic pressure in the hydraulic chamber 12 can be controlled more precisely.

The solenoid valve 2, the motor 6, the potentiometer 40, and the hydraulic pressure sensor 41 are an electronic control unit (ECU) 7.
The electronic control unit 7 is connected to the hydraulic pressure sensor 41,
The motor 6 is rotated and driven based on signals from the potentiometer 40 and various sensors (not shown), and the solenoid valve 2 is operated to control the hydraulic pressure in the hydraulic control circuit in a manner described later. A power motor (power type small motor capable of forward and reverse rotation) is used as the above-mentioned motor 6, and the rotation angle of the motor can be controlled by a signal from the potentiometer 40.

In the above example, the power motor is used as the motor 6 and the motor is controlled by the position signal from the potentiometer 40. However, the servo is used as the motor without using the potentiometer as described above. Although it is possible to use a motor and control the rotation of the motor by an encoder, in this case, the cost is higher because the servo motor uses the encoder. Reference numeral 42 in the drawing is a cover.

The operation of the hydraulic pressure control device having the above configuration will be described. [Normal Operation State] In a normal state, there is no command from the electronic control unit 7, and the solenoid valve 2 and the motor 6 do not operate. The pressure adjusting piston 20 is in the initial position shown in FIG. Therefore, in this state, when hydraulic pressure is generated in the hydraulic pressure generation source 1, this hydraulic pressure is supplied to the flow passage 30 → opened solenoid valve 2 → hydraulic chamber 12 → passage 31 → actuator to operate the actuator. To do. When the hydraulic pressure of the hydraulic pressure generation source is released, the liquid in the actuator is returned to the hydraulic pressure generation source by the route opposite to the above, and the actuator returns to the initial position.

[Hydraulic Pressure Control in the Hydraulic Pressure Control Circuit] When controlling the hydraulic pressure in the hydraulic pressure circuit, the electronic control unit 7 is operated based on signals from the hydraulic pressure sensor 41 and other sensors (not shown). Rotates the motor 6 and closes the solenoid valve 2. By driving the motor 6, the pinion 24 and the large gear 2
The gear shaft 15 is rotated counterclockwise in FIG.
The rotation of the gear shaft 15 also rotates the gear 22, and the pressure adjusting piston 20 gradually sinks into the piston housing window 17 via the rack 20a meshing with the gear 22. As a result, the volume in the hydraulic chamber 12 is increased, the hydraulic pressure in the hydraulic circuit is reduced, and the hydraulic pressure acting on the actuator is reduced.

Further, at the time of repressurization, when the motor 6 is rotated in the reverse direction and the gear shaft 15 is rotated in the direction of the initial position, the pressure adjusting piston 20 is pushed back into the hydraulic chamber 12 and repressurization is executed. At this time, the rotation of the motor 6 is controlled by the electronic control unit 7 based on the signal from the potentiometer 40. Therefore, the motor can use a normal power motor,
It is not necessary to use a servomotor with an encoder or the like, and the cost of the entire device can be reduced.

As described above, in this example, since the hydraulic pressure control device is independently configured, the brake circuit and any other hydraulic pressure circuit can be arranged in any hydraulic circuit as needed. It is possible to smoothly increase and decrease the hydraulic pressure of. In addition, in the above-described embodiment, the description is given by taking a case where a pair of pressure regulating pistons are provided as an example, but the number of pressure regulating pistons may be one, and if necessary, an appropriate number of three or more pressure regulating pistons. Can also be

Next, a second embodiment of the present invention will be described with reference to FIG. The second embodiment is characterized in that the above-mentioned hydraulic control device is arranged in a brake caliper. In addition,
The description of the present embodiment will focus on the differences from the first embodiment. In FIG. 3, 1 is a master cylinder as a hydraulic pressure generation source, 2 is a solenoid valve, 3 is a hydraulic pressure control device arranged in a brake caliper, 4 is a brake piston as an actuator provided in the hydraulic pressure control device, and 5 is A disc pad, 6 is a motor for driving the hydraulic control device, 7 is an electronic control unit (ECU), and 30 is a flow path, and these constitute a brake system. A cylinder 11 is formed in the main body 10 of the hydraulic control device 3 (in the case of this example, the caliper of the disc brake also serves as this).
The brake piston 4 is slidably arranged in the cylinder 11. As well known, a disc pad 5 is attached to the brake piston 4.

The cylinder 11 and the brake piston 4 form a hydraulic pressure chamber 12, and this hydraulic pressure chamber 12 is connected to a master cylinder 1 as a hydraulic pressure generation source via an electromagnetic valve 2 provided in a flow passage 30. It is in communication. A gear case 13 is arranged in the hydraulic chamber 12, and the gear case 13 is fixed to the main body 10 in a liquid-tight state 14. At the center of the gear case 13, a hydraulic pressure control mechanism 3 including a gear shaft 15, a pressure adjusting piston 20 and a piston housing window 17 similar to that described in the first embodiment is arranged. A large gear 23 is fixed to the gear, and the large gear 23 meshes with a pinion 24 attached to the output shaft of the motor 6, which constitutes a gear drive mechanism. Further, as in the case of the first embodiment, the flexible boot 25 is provided around the gear case 13 to prevent the brake fluid in the hydraulic chamber 12 from leaking out from the piston housing window 17. There is.

The solenoid valve 2 and the motor 6 described above are connected to an electronic control unit (ECU) 7. The electronic control unit 7 has a speed sensor (not shown), a potentiometer (not shown in FIG. 3), etc. The motor 6 is rotationally driven on the basis of the signal from and the solenoid valve 2 is operated to execute the antilock control in a manner described later. In the figure, reference numeral 26 denotes a seal member between the brake piston 4 and the main body 10.

The operation of the brake device having the above structure will be described. [Normal Braking] During normal braking, there is no command from the electronic control unit 7 and the solenoid valve 2 and the motor 6 do not operate. The gear is in the initial position shown in FIG. Therefore, in this state, when the brake pedal is depressed to generate hydraulic pressure in the master cylinder 1, this hydraulic pressure is supplied to the hydraulic pressure chamber 12 through the master cylinder 1 → opened solenoid valve 2 → passage 30 and brakes. The piston 4 is moved to execute the braking action. At this time, the pressure adjusting piston 20 does not move because the gear shaft 15 does not rotate. When the depression of the brake pedal is released, the brake fluid in the hydraulic chamber is returned to the master cylinder in the route opposite to the above, and the brake is released.

[Anti-Lock Control] When the brake pedal is depressed to brake the vehicle, the master cylinder 1
Causes hydraulic pressure. This hydraulic pressure is supplied to the hydraulic chamber 12 in the brake device as described above, and moves the brake piston 4 to apply a braking force to the wheels. By the way, in this state, the state of the wheels is always detected by a speed sensor or the like, and the detection signal is input to a known electronic control unit, and the electronic control unit is based on this input, the wheel speed, the slip ratio, and the deceleration. And so on. Then, the skid state of the wheels is evaluated based on this calculation result, and the solenoid valve 2 and the motor 6 are controlled as described below to execute various modes such as depressurization, holding, and repressurization of the brake fluid pressure.

That is, when the wheels are locked during running and the brake release signal is output from the electronic control unit (ECU) 7, the solenoid valve 2 is closed and the motor 6 is driven, and the pinion 24 and the large gear 23 are used. Gear shaft (see Fig. 2) 1
Rotate 5 counterclockwise. By the rotation of the gear shaft 15,
The gear 22 also rotates, and accordingly, the pressure adjusting piston 20 gradually sinks into the piston housing window 17, and as a result, the volume in the hydraulic chamber 12 increases 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 repressurization, when the motor 6 is rotated in the reverse direction and the gear shaft is rotated in the direction of the initial position, the pressure adjusting piston is pushed back into the hydraulic chamber 12 and repressurization is executed. Further, when a command for holding the brake fluid pressure is issued, the motor 6 stops and holds the brake fluid pressure in the fluid pressure chamber.

The hydraulic pressure control (pressure reduction, holding, re-pressurization) of the brake device is performed independently or for each wheel of each channel according to the state of each wheel. The release of the antilock control is performed when there is no signal from the electronic control unit. That is, when the signal from the electronic control unit disappears, the solenoid valve 2 opens and the motor 6 returns the gears to the initial position.
0 also returns to the initial position and enters the state shown in FIG. 3, which is the normal braking state.

If the relationship between the gear and the rack 20a provided on the pressure adjusting piston 20 is appropriately set, the pressure adjusting piston 20 causes the gear adjusting shaft 20 to protrude from the gear case 13 with respect to the initial position. When it is rotated to, the hydraulic pressure in the hydraulic chamber can be increased, whereby automatic braking and traction control can be executed. When the gear shaft 15 is rotated in the direction in which the pressure adjusting piston 20 is submerged in the gear case 13 based on the initial position, the hydraulic pressure in the hydraulic chamber can be reduced as described above. This enables anti-lock control to be executed.

For example, when the wheels slip when starting the vehicle, or when the inter-vehicle distance becomes short, the electromagnetic valve 2 is closed and the gear shaft 15 is adjusted by the pressure adjusting piston 20.
Is rotated in a direction to push it into the fluid pressure chamber 12, the brake fluid pressure in the fluid pressure chamber 12 is increased, and the wheel is braked.
In traction control, the state of the wheels is constantly detected by a speed sensor, and a detection signal is input to a known electronic control device, and the electronic control device calculates wheel speed, slip rate, deceleration, etc. based on the input. I do. Then, the slip state of the wheel is evaluated based on this calculation result, the solenoid valve 2 and the motor 6 are controlled, and various modes such as depressurization, holding, and repressurization of the brake fluid pressure are executed similarly to the above-described antilock control. .

When an inter-vehicle distance sensor (not shown) detects that the inter-vehicle distance is within a predetermined value, the electromagnetic valve 2 and the motor 6 are controlled by a signal from the electronic control unit to increase the brake fluid pressure. Various modes such as holding, holding, and depressurizing can be executed to activate the automatic braking. As described above, according to the present embodiment, the pressure in the hydraulic chamber 12 is controlled by the pressure adjusting piston that moves with the rotation of the gear shaft 15, so that the brake hydraulic pressure is reduced and maintained according to the brake operation mode. , Repressurization can be performed. As described above, in this example, since the hydraulic pressure control device is provided in the brake caliper, the size and weight of the brake device can be reduced, and the increase and decrease of the brake hydraulic pressure can be smoothly performed.

[0034]

As described above in detail, according to the present invention, the pressure adjusting piston is arranged in the hydraulic chamber formed in the main body of the hydraulic pressure control device, and the moving amount of the pressure adjusting piston is utilized by the rack and pinion mechanism. By controlling, the volume of the hydraulic chamber can be controlled and the hydraulic pressure acting on the actuator can be increased or decreased. Further, in the brake device configured by incorporating this hydraulic pressure control device into the brake caliper, it is possible to smoothly perform antilock control, traction control and automatic brake control, and further reduce the size and weight of the brake device. it can. In addition, because the mechanism that allows the pressure adjusting piston to move in and out of the hydraulic chamber by the meshing of the gear on the gear shaft and the rack on the pressure adjusting piston, accurate torque transmission is achieved, and the amount of movement of the pressure adjusting piston is precise. To
In addition, smooth control is possible, optimal hydraulic pressure control is possible, and noise during control can be reduced. In addition, the brake device built into the caliper can reduce the weight under the spring of the vehicle suspension.In addition, if the potentiometer is used to detect the rotation angle of the gear and the motor can be controlled, No need for a high-priced encoder to control the cost of the device, and the cost of the device as a whole can be reduced.When the hydraulic pressure control device is built into the caliper, piping etc. are not required, and there is no loss due to piping. It is possible to achieve excellent operational effects such as.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a hydraulic pressure control device as a first embodiment according to the present invention.

FIG. 2 is a view on arrow AA in FIG.

FIG. 3 is a schematic configuration diagram of a brake device as a second embodiment according to the present invention.

[Explanation of symbols] 1 hydraulic pressure generation source (master cylinder) 2 solenoid valve 3 hydraulic pressure control device 4 brake piston 5 disc pad 6 motor 7 electronic control device 10 main body 11 cylinder 12 hydraulic chamber 13 gear case 15 gear shaft 16 long Hole 17 Piston storage window 18, 19 Bearing 20 Pressure regulating piston 22 Gear 25 Boot 40 Potentiometer 41 Liquid pressure sensor

Claims (4)

[Claims] 1. A hydraulic pressure control device (3) arranged in a hydraulic pressure circuit between a hydraulic pressure generation source (1) and an actuator, for controlling hydraulic pressure acting on the actuator, the device being the hydraulic pressure control device (3). Cylinder 1 formed on the controller body
1, a hydraulic pressure chamber 12 formed in the cylinder 11 and communicating with the hydraulic pressure generation source 1 and an actuator, a gear case 13 arranged in the hydraulic pressure chamber 12, and a gear case 13 arranged in the gear case 13. Gear shaft 15, a motor 6 that rotates the gear shaft 15, a pressure adjusting piston 20 that projects in and out of the hydraulic chamber 12 by the rotation of the gear shaft 15, the inside of the hydraulic chamber 12, and the hydraulic pressure. Flow path 30 communicating with the generation source 1
A hydraulic control device comprising: an electromagnetic valve 2 disposed inside; and an electronic control unit (ECU) 7 that controls the electromagnetic valve 2 and the motor 6. 2. A gear provided on the gear shaft 15 meshes with a rack formed on the pressure adjusting piston, and the pressure adjusting piston appears and disappears in the hydraulic chamber in accordance with the rotation of the gear, thereby reducing the pressure in the hydraulic chamber, The fluid pressure control device according to claim 1, which controls holding and pressurization. 3. A cylinder 11 formed in a caliper of a brake device, a slidable brake piston 4 arranged in the cylinder 11, and a hydraulic chamber 12 defined in the cylinder 11 by the piston. The gear case 13 arranged in the hydraulic chamber 12, the gear shaft 15 arranged in the gear case 13, the motor 6 for rotating the gear shaft 15, and the rotation of the gear shaft 15 cause the liquid A pressure adjusting piston 20 that appears in and out of the pressure chamber 12, and a flow path 30 that connects the inside of the hydraulic chamber 12 and the hydraulic pressure generation source 1 to each other.
A brake device, comprising: an electromagnetic valve 2 disposed inside; and an electronic control unit (ECU) 7 that controls the electromagnetic valve 2 and the motor. 4. A gear provided on the gear shaft 15 meshes with a rack formed on the pressure adjusting piston, and the pressure adjusting piston moves into and out of the hydraulic chamber in response to the rotation of the gear to reduce the pressure in the hydraulic chamber. The brake device according to claim 3, which controls holding and pressurization.