JPH08284981A - Disk brake device - Google Patents

Abstract

PURPOSE: To provide a disk brake capable of keeping the sure braking performance, constituting two different brake systems, and miniaturizing the device with a simple structure. CONSTITUTION: A disk brake device 10 is provided with a torque converting mechanism 42 and an ultrasonic motor 70. A supporting shaft 54 of an operation lever 52 is inserted in a core part of a screw shaft 46 of the torque converting mechanism part 42 in a relatively movable manner only in the axial direction. During the normal braking, the screw shaft 46 is moved in the axial direction by the ultrasonic motor 70, and an inner pad 14 is pressed to generate the braking force. When the operation lever 52 (the supporting shaft 54) is turned, the screw shaft 46 is moved in the axial direction while being turned, and the inner pad 14 is pressed to be in the braking condition, and can be used as the parking brake.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disc brake device in which a brake pad is pressed against a disc rotor to generate a braking force.

[0002]

2. Description of the Related Art Among disc brake devices having a structure in which a disc rotor is sandwiched between a pair of brake pads for braking, a disc brake device using an ultrasonic motor as a drive source is known (as one example, Japanese Patent Laid-Open No. Hei 5 (1999) -135945). -321961
Issue).

In this type of disc brake device, an ultrasonic motor is built in a caliper housing, and the ultrasonic motor is connected to a piston by a rotational force converting mechanism such as a screw rod. further,
A push rod, a parking lever and the like are attached to the caliper housing and are linked to the ultrasonic motor.

In this disc brake device, when the brake is actuated, the piston is moved by the drive of the ultrasonic motor to press the brake pad to generate a braking force, and an electric actuator using a wire wound motor as a drive source is used. Compared with the conventional configuration, the ultrasonic motor itself has advantages such as small size and low power consumption. Further, when the vehicle is stopped, the parking motor is operated to forcibly move the ultrasonic motor in the caliper housing along the axial direction, and the piston is moved together with the torque conversion mechanism to move the brake pad. Can be pressed.

As described above, in the disc brake device disclosed in the above publication, not only the first brake system that is normally used when the vehicle is running, but also the second brake system that is used when the vehicle is stopped.
There is an advantage that the brake system (parking brake) can be configured in a single device.

However, in such a conventional disc brake device, an ultrasonic motor as a drive source, a rotational force conversion mechanism for converting the rotational force of the ultrasonic motor into a linear movement force, or the ultrasonic motor is forced. Since the moving mechanism (parking brake mechanism) for moving the piston together with the rotational force converting mechanism is separated and independent from each other, the disk brake device as a whole is large and heavy.

Further, in the disc brake device, the ultrasonic motor must be prevented from moving in the axial direction in the first brake system that is normally used when the vehicle is running, while it is used when the vehicle is stopped. In the parking brake system, the ultrasonic motor must be constructed so as to be blocked in rotation and axially movable. Therefore, each mechanism is complicated, which also causes a large and heavy apparatus as a whole.

Further, in a mechanism (parking brake mechanism) for forcibly moving the ultrasonic motor to bring it into the brake operating state, the ultrasonic motor is forcibly moved by operating the parking lever, and the rotational force is increased. Although it is configured to move the piston together with the conversion mechanism to press the brake pad, in order to reliably press the brake pad to bring it into the brake operating state, an extremely large operating force is required, and the parking brake is brought into the operating state. That was extremely difficult in reality.

[0009]

SUMMARY OF THE INVENTION In consideration of the above facts, the present invention allows two different braking systems independent from each other to be constructed in a single device while maintaining reliable braking performance. An object of the present invention is to obtain a disc brake device that can be realized with a simple structure and a small size.

[0010]

According to another aspect of the present invention, there is provided a disc brake device in which a brake pad is pressed against a disc rotor to generate a braking force. An electric motor, a nut to which the electric motor is connected, and a screw shaft that is combined with the nut by a ball screw and is provided so as to face the brake pad. The rotating force of the electric motor is applied to the screw shaft. Is converted into an axial direction moving force of the screw shaft, and is connected to a torque conversion mechanism section that presses the brake pad by the axial direction moving force of the screw shaft, and a screw shaft of the torque conversion mechanism section, and is independent of the operation of the electric motor. Force the screw shaft to rotate and move it in the axial direction. And forcible movement means is characterized by comprising a.

A disc brake device according to a second aspect of the present invention is the disc brake device according to the first aspect,
The electric motor includes a rotor connected to the nut,
The ultrasonic motor comprises a stator fixed to the housing so as to face the rotor, and an urging member that presses the rotor into pressure contact with the stator.

A disc brake device according to a third aspect of the present invention is the disc brake device according to the first aspect,
The torque conversion mechanism section includes a worm wheel connected to the nut, and a worm gear that is provided on the rotation shaft of the electric motor and meshes with the worm wheel.

A disc brake device according to a fourth aspect of the present invention is the disc brake device according to any one of the first, second or third aspects, wherein the forcibly moving means is provided at an axial center portion of the screw shaft. It is characterized by comprising a support hole and an operating lever having a support shaft formed therein, the support shaft being prevented from rotating relative to the support hole and being relatively movable in the axial direction.

[0014]

In the disc brake device according to the first aspect of the present invention, when the electric motor is actuated by the brake operation, the torque converting mechanism converts the torque of the electric motor into the axial moving force of the screw shaft, so that the screw shaft moves in the axial direction. When the brake pad is moved, the brake pad is pressed and a braking force is generated.

Further, since the electric motor is immovable by an external input to its rotating portion, the axial moving force of the screw shaft of the torque converting mechanism is temporarily input to the rotating portion of the electric motor via the nut as an external input. Even if it works, the electric motor does not move. In other words, rotation of the nut of the torque conversion mechanism is blocked when the electric motor is not operating,
The screw shaft is also prevented from moving in the axial direction. Therefore, the brake operating state can be maintained (the parking brake operating state) by stopping the electric motor while the brake pad is being pressed while the vehicle is stopped, for example.

On the other hand, when the forcible moving means is operated while the electric motor is not operating, the screw shaft of the torque converting mechanism is forcibly rotated. Here, when the electric motor is not operating, the rotation of the nut of the torque conversion mechanism is blocked as described above, and therefore, when the screw shaft is forcibly rotated, the screw shaft itself moves along the axial direction. Move and press the brake pads. As a result, the brake is activated. That is,
The brake can be activated by operating the forced moving means. Therefore, for example, when the forced moving means is operated while the vehicle is stopped, the parking brake can be activated. Further, when the forced moving means is operated when the electric motor is not operated (when the vehicle is running), it can be used as an emergency brake.

As described above, in the disc brake device according to the first aspect, not only the first brake system by the driving force of the electric motor but also the second brake system by the forced moving means may be configured in a single device. You can

Also, since the electric motor is connected to the nut of the torque conversion mechanism section for converting the rotational force into the linear movement force, which is formed of a ball screw, and the electric motor and the torque conversion mechanism section are integrated, the device Becomes compact as a whole.

Further, even in the second brake system by the forced moving means, the mechanism does not become complicated because the screw shaft of the torque converting mechanism is rotated. Further, since the rotational force is converted into the linear movement force by the ball screw, a large operating force is not required, and the brake operating state can be reliably achieved.

As described above, in the disc brake device according to the first aspect of the present invention, it is possible to configure two different brake systems independent of each other in a single device while maintaining a reliable brake operation performance. Can be realized with a simple structure and a small shape.

In the disc brake device according to the second aspect, when the ultrasonic motor is actuated by the braking operation, the rotational force of the rotor of the ultrasonic motor is converted into the axial moving force of the screw shaft by the torque conversion mechanism portion, and the screw shaft. Moves in the axial direction, the brake pad is pressed, and a braking force is generated.

Further, in the ultrasonic motor, the rotor is restrained by the self-holding force in the inoperative state. Therefore, when the ultrasonic motor is inoperative, the nut of the torque converting mechanism is prevented from rotating, and the screw shaft is also prevented from moving in the axial direction. Therefore, the brake operating state is maintained (the parking brake operating state) by stopping the ultrasonic motor while the brake pad is being pressed while the vehicle is stopped, for example.
be able to.

On the other hand, when the ultrasonic motor is not operating,
When the forced moving means is activated, the screw shaft of the torque conversion mechanism unit is forcibly rotated. Here, when the ultrasonic motor is not in operation, the rotation of the nut of the torque conversion mechanism is blocked as described above. Therefore, when the screw shaft is forcibly rotated, the screw shaft itself moves along the axial direction. To move and press the brake pad. As a result, the brake is activated. That is, the brake can be activated by the operation of the forced moving means. Therefore, for example, when the forced moving means is operated while the vehicle is stopped, the parking brake can be activated. Further, when the forced movement means is operated when the ultrasonic motor is not operating (when the vehicle is running), it can be used as an emergency brake.

As described above, in the disc brake device according to the second aspect, not only the first brake system by the driving force of the ultrasonic motor but also the second brake system by the forced moving means are configured in a single device. be able to.

Further, the rotor of the ultrasonic motor is directly connected to the nut of the torque converting mechanism which is composed of a ball screw and converts the rotational force into the linear moving force, and the ultrasonic motor and the torque converting mechanism are integrated. Therefore, the device becomes compact as a whole.

Further, even in the second brake system by the forced moving means, the mechanism is not complicated because the screw shaft of the torque converting mechanism is rotated. Further, since the rotational force is converted into the linear movement force by the ball screw, a large operating force is not required, and the brake operating state can be reliably achieved.

As described above, in the disc brake device according to the second aspect of the present invention, two different brake systems independent of each other can be configured in a single device while maintaining a reliable brake operation performance, and Can be realized with a simple structure and a small shape.

In the disc brake device according to the third aspect, when the electric motor is actuated by the brake operation, the rotational force of the electric motor is transmitted to the nut via the worm gear and the worm wheel of the torque conversion mechanism portion, and further,
The force is converted into an axial movement force of the screw shaft, the screw shaft moves in the axial direction, the brake pad is pressed, and a braking force is generated.

Since the worm gear provided on the rotary shaft of the electric motor meshes with the worm wheel,
The transmission of external input from the worm wheel to the rotary shaft of the electric motor via the worm gear is cut off. That is,
The electric motor is restrained by the worm gear and the worm wheel in the non-operating state. For this reason,
When the electric motor is not operating, the nut of the torque converting mechanism is prevented from rotating, and the screw shaft is also prevented from moving in the axial direction. Therefore, the brake operating state can be maintained (the parking brake operating state) by stopping the electric motor while the brake pad is being pressed while the vehicle is stopped, for example.

On the other hand, when the forcible moving means is operated when the electric motor is not in operation, the screw shaft of the torque converting mechanism is forcibly rotated. Here, when the electric motor is not operating, the rotation of the nut of the torque conversion mechanism is blocked as described above, and therefore, when the screw shaft is forcibly rotated, the screw shaft itself moves along the axial direction. Move and press the brake pads. As a result, the brake is activated. That is,
The brake can be activated by operating the forced moving means. Therefore, for example, when the forced moving means is operated while the vehicle is stopped, the parking brake can be activated. Further, when the forced moving means is operated when the electric motor is not operated (when the vehicle is running), it can be used as an emergency brake.

As described above, in the disc brake device according to the third aspect, not only the first brake system by the driving force of the electric motor but also the second brake system by the forced moving means may be configured in a single device. You can

Further, a worm wheel is connected to a nut of a torque converting mechanism which is composed of a ball screw and converts a rotational force into a linear moving force, and a worm gear provided on a rotating shaft of an electric motor is meshed with the worm wheel. Therefore, the device becomes compact as a whole.

Further, even in the second brake system by the forced moving means, the mechanism is not complicated because the screw shaft of the torque converting mechanism is rotated. Further, since the rotational force is converted into the linear movement force by the ball screw, a large operating force is not required, and the brake operating state can be reliably achieved.

As described above, in the disc brake device according to the third aspect of the present invention, two different brake systems independent of each other can be configured in a single device while maintaining a reliable brake actuation performance. Can be realized with a simple structure and a small shape.

According to another aspect of the disc brake device of the present invention, the support shaft formed on the operation lever constituting the forced movement means is relatively rotated within the support hole provided in the axial center portion of the screw shaft of the torque conversion mechanism. Are blocked and enter relative movement in the axial direction. Therefore, when the electric motor (ultrasonic motor, DC motor) operates when the forced moving means is inactive, the rotation of the screw shaft is blocked, the rotational force of the nut is converted into the axial moving force of the screw shaft, and the screw shaft is rotated. Moves in the axial direction relative to the operation lever, the brake pad is pressed, and a braking force is generated.

On the other hand, when the forced movement means is operated, the screw shaft is forcibly rotated together with the operation lever, and the screw shaft itself moves in the axial direction to press the brake pad. As a result, the brake is activated.

Here, since the forced moving means is provided at the axial center portion of the screw shaft of the torque converting mechanism portion, the apparatus as a whole becomes compact.

[0038]

1 is a sectional view of a disc brake device 10 according to a first embodiment of the present invention.

In the disc brake device 10, an inner pad 14 and an outer pad 16 are attached to a mounting bracket (not shown) inside the caliper housing 12. The inner pad 14 and the outer pad 16 are provided so as to face a disc rotor 18 that rotates together with the wheels, and the inner pad 14 and the inner pad 14 are provided on the inner side of the vehicle.
Are located on the outer side of the vehicle, and the outer pad 16 is located on the outer side of the vehicle. The caliper housing 12 covers the inner pad 14 and the outer pad 16 from above,
The claw portion 20 receives a force acting outward from the outer pad 16.

On the other hand, an electric actuator 30 is provided on the side of the inner pad 14. The electric actuator 30 includes a housing 32 and a cover 34 fixed to the housing 32, and the cover 34 is integrally fixed to a flange portion 38 of the caliper housing 12 by a bolt 36.

A torque conversion mechanism portion 42 is provided inside the housing 32 and the cover 34. The torque conversion mechanism section 42 is configured by a nut 44 and a screw shaft 46, and the nut 44 and the screw shaft 46 are combined by a ball screw 48. The nut 44 is covered by the bearing 62.
4, a thrust bearing 68 is interposed between the nut 44 and the housing 32. Therefore, when the nut 44 rotates in a state where the rotation of the screw shaft 46 itself is blocked, the rotational force is transmitted to the screw shaft 46 by the ball screw 48, and the screw shaft 46 is moved in the axial direction. When the screw shaft 46 rotates while the rotation of the nut 44 is blocked, the ball screw 48 moves the screw shaft 46 itself in the axial direction.

A flange portion 64 is formed around the nut 44 in the vicinity of the bearing 62. Further, in the axial center portion of the screw shaft 46, the support hole 5 having a shape such as a square or a spline groove which constitutes the forced moving means is formed.
0 is formed. In the support hole 50, the support shaft 54 of the operation lever 52 which also constitutes the forced movement means.
Is inserted, and the screw shaft 46 is movable relative to the support shaft 54 in the axial direction.

A shaft 53 of the operating lever 52 is rotatably supported by the housing 32 by a bearing 55, and a support shaft 54 is formed coaxially with the shaft 53. The support shaft 54 is formed in a shape corresponding to the support hole 50, such as a square shape or a spline shaft. Therefore, the screw shaft 46 is prevented from rotating relative to the operating lever 52 and can move only in the axial direction.

Further, as shown in FIG. 2, a flange portion 57 is formed on the operation lever 52 and corresponds to the stopper 33 formed on the housing 32. Therefore, the operation lever 52 is configured so that its rotation is restricted by the flange portion 57 engaging with the stopper 33. further,
The operation lever 52 is biased by a spring (not shown) in a direction in which the flange portion 57 engages with the stopper 33 (direction of arrow A in FIG. 2). One end of an operation rod 59 is connected to the operation lever 52, and the other end of the operation rod 59 is connected to a parking brake lever (not shown).

When the nut 44 is fixed (rotation is prevented), the operating lever 52 (screw shaft 46) rotates in the direction of arrow B in FIG. 2 so that the screw shaft 46 moves in the axial direction (in the inner pad 14). The screw groove of the ball screw 48 is set so as to move in the approaching direction).

A thrust sensor 58 is fixed to the tip of the screw shaft 46 on the side opposite to the operating lever 52 via a plate 56. The thrust sensor 58 is in contact with the inner pad 14, and the lead wire 60 of the thrust sensor 58 is guided to the outside via the screw shaft 46 and the shaft center portion of the support shaft 54 of the operation lever 52. As a result, when the screw shaft 46 is moved in the axial direction, the plate 56 and the thrust sensor 58 are
The inner pad 14 is pressed via the, and the pressing force at this time is detected by the thrust sensor 58.

On the other hand, the torque converting mechanism 42 (nut 4
An ultrasonic motor 70 is provided around 4). The ultrasonic motor 70 is composed of a stator 72, a rotor 74, and a disc spring 76 as a biasing member.

The stator 72 is fixed to the housing 32. The rotor 74 is provided on the opposite side of the stator 72 from the operation lever 52, and is connected to the nut 44 via a key or the like (not shown).
As a result, the rotor 74 is configured to rotate together with the nut 44 and move relative to the nut 44 in the axial direction. A disc spring 76 is arranged laterally of the rotor 74 with a plate 84 interposed. This disc spring 76 is
The center-side end portion is supported by the flange portion 64 of the nut 44 via the spacer 88 for adjusting the pressing force, and always presses the rotor 74 toward the stator 72. For this reason,
The rotor 74 is constantly pressed against the stator 72 with a predetermined pressure.

Next, the operation of the first embodiment will be described. In the disc brake device 10 including the electric actuator 30 having the above configuration, the electric actuator 30 (the ultrasonic motor 7
0) is inoperative, and the screw shaft 46 (thrust force sensor 58) does not press the inner pad 14. Therefore, a gap is formed between each of the inner pad 14, the outer pad 16 and the disc rotor 18,
The disc rotor 18 is unrestrained.

On the other hand, when the brake is operated by operating the brake pedal (not shown), the ultrasonic motor 70 is operated. That is, the rotor 74 is rotated by the traveling wave generated in the stator 72 by applying a predetermined voltage, and the nut 44 is rotated together with the rotor 74. The rotational force of the nut 44 is transmitted to the screw shaft 46 by the ball screw 48, and the screw shaft 46 is moved in the axial direction. When the screw shaft 46 is moved in the axial direction, the plate 56 and the thrust sensor 58
The inner pad 14 is pressed via the inner pad 1
4 is pressed against the disc rotor 18 to generate a frictional force therebetween, and a braking torque acts on the disc rotor 18. Furthermore, at the same time as the screw shaft 46 moves in the axial direction,
The caliper housing 12 itself is moved in the direction away from the disc rotor 18, and the claw portion 20 moves.
The outer pad 16 is moved in the direction of 8 to press the outer pad 16, and the outer pad 16 is pressed against the disc rotor 18 to generate a frictional force between them and a braking torque acts on the disc rotor 18.

Further, when the screw shaft 46 moves in the axial direction and presses the pressure plate 22, this pressing force is detected by the thrust sensor 58, and the pressing force (braking force) corresponding to the brake operating force is detected. The drive of the ultrasonic motor 70 is controlled so that

In this case, when the inner pad 14 is pressed by the movement of the screw shaft 46, a rotational torque acts on the screw shaft 46 by the reaction force from the inner pad 14 in the rotation direction of the nut 44 (direction of arrow A in FIG. 2). To do. However, since the screw shaft 46 is connected to the support shaft 54 of the operation lever 52 and the operation lever 52 is prevented from rotating by the stopper 33 of the housing 32, the pressing force of the screw shaft 46 on the inner pad 14 changes ( It does not decrease).

Further, in the ultrasonic motor 70, the rotor 74 is restrained by the self-holding force in the inoperative state. Therefore, when the ultrasonic motor 70 is not operating, the nut 44 of the torque converting mechanism 42 is prevented from rotating, and the screw shaft 46 is also prevented from moving in the axial direction. Therefore, for example, when the vehicle is stopped, the ultrasonic motor 70 is stopped while the inner pad 14 and the outer pad 16 are kept in pressure contact with the disc rotor 18, so that the brake operating state is maintained (the parking brake operating state is set). )be able to.

On the other hand, when the parking brake lever is operated while the ultrasonic motor 70 is inactive, the operation lever 52 is forcibly rotated in the direction of arrow B in FIG. 2 via the operation rod 59. Therefore, the screw shaft 46 connected to the operation lever 52 by the support shaft 54
Is similarly forcedly rotated in the direction of arrow B in FIG. Here, in the non-operating state of the ultrasonic motor 70, the rotor 74 is in a stationary state due to the self-holding force as described above, and the rotation of the nut 44 of the torque conversion mechanism portion 42 is blocked. Therefore, when the screw shaft 46 is forcibly rotated, the screw shaft 46 itself moves along the axial direction while rotating, and presses the inner pad 14 via the plate 56 and the thrust sensor 58. As a result, the brake is activated. That is, by operating the operation lever 52, the brake can be activated.

Therefore, for example, when the operation lever 52 is operated while the vehicle is stopped, the parking brake can be activated. In addition, the ultrasonic motor 70
When the operating lever 52 is operated when the vehicle is not operating (when the vehicle is running), it can be used as an emergency brake.

As described above, in the disc brake device 10, not only the first brake system operated by the driving force of the ultrasonic motor 70 but also the second brake system operated by the rotation of the operation lever 52 (support shaft 54). Can be configured in a single device.

Further, the rotor 74 of the ultrasonic motor 70 is directly connected to the nut 44 of the torque converting mechanism portion 42, which is composed of the ball screw 48 and converts the rotational force into the linear moving force, and the ultrasonic motor 70 and the torque converting mechanism portion are connected. The device is compact as a whole because of the configuration in which 42 and 42 are integrated.

Further, the operating lever 52 (support shaft 5
Also in the second brake system according to 4), since the operation lever 52 (support shaft 54) is configured to rotate the screw shaft 46 of the torque conversion mechanism unit 42 (in other words, actuated by the driving force of the ultrasonic motor 70). Since the configuration of the first brake system is used as it is), the mechanism does not become complicated. Further, since the rotational force is converted into the axial moving force by the ball screw 48, a large operating force is unnecessary and the parking brake operating state can be reliably achieved.

As described above, in the disc brake device 10 according to the first embodiment, two different brake systems independent of each other can be configured in a single device while maintaining the reliable brake operation performance. Moreover, this can be realized with a simple structure and a small shape.

Further, in the disc brake device 10 according to the first embodiment, the nut 44 of the torque conversion mechanism portion 42 is used.
In order to convert the rotational force of the screw shaft 46 into the axial movement force of the screw shaft 46 (normally a structure that blocks the rotation of the screw shaft 46), and to forcibly rotate the screw shaft 46 of the torque conversion mechanism unit 42, A supporting hole 50 is provided in the screw shaft 41, and the supporting shaft 54 of the operating lever 52 is inserted into the supporting hole 50,
The screw shaft 46 is configured so that relative rotation is blocked and the screw shaft 46 can move only in the axial direction. That is,
Since the mechanism for preventing the rotation of the screw shaft 46 and allowing the screw shaft 46 to slide only in the axial direction is provided in the axial center portion of the screw shaft 46, no extra space is required and the overall size can be reduced.

Next, another embodiment of the present invention will be described. The parts that are basically the same as those in the first embodiment have the first
The same reference numerals as in the embodiment are given and the description thereof is omitted.

FIG. 3 is a sectional view of a disc brake device 90 according to the second embodiment of the present invention.

The disc brake device 90 is provided with an electric actuator 92. The electric actuator 92 is the ultrasonic motor 70 of the disc brake device 10 (electric actuator 30) according to the first embodiment described above.
Instead, a DC motor 94 is provided. A worm gear 98 is provided on the rotating shaft 96 of the DC motor 94, and the worm gear 98 is the worm wheel 1.
It meshes with 00. The worm wheel 100 is located around the nut 44 of the torque conversion mechanism unit 42, and is connected to the nut 44 via the key 102.
As a result, the worm wheel 100 is configured to rotate together with the nut 44.

In the disc brake device 90 according to the second embodiment, when the brake operation is performed and the DC motor 94 is operated, the worm gear 98 and the worm wheel 10 are operated.
The rotational force is transmitted via 0 to rotate the nut 44. The rotational force of the nut 44 is transmitted to the screw shaft 46 by the ball screw 48, and the screw shaft 46 is moved in the axial direction. As a result, the inner pad 14 is pressed and brought into pressure contact with the disc rotor 18, and a frictional force is generated between the inner pad 14 and the disc rotor 18 to exert a braking torque on the disc rotor 18. Further, at the same time as the screw shaft 46 moves in the axial direction, the caliper housing 12 itself is moved in a direction away from the disc rotor 18, and the pawl portion 2
0 is moved toward the disc rotor 18 and presses the outer pad 16, so that the outer pad 16 moves
8 is pressed against each other to generate a frictional force therebetween, and the disc rotor 1
Braking torque acts on 8.

Also in this case, even if a rotational torque acts on the screw shaft 46 in the rotational direction of the nut 44 due to the reaction force from the inner pad 14, the screw shaft 4
Reference numeral 6 is connected to the support shaft 54 of the operation lever 52, and the operation lever 52 is prevented from rotating by the stopper 33 of the housing 32. Therefore, the pressing force of the screw shaft 46 on the inner pad 14 is changed (decreased). There is no.

Further, since the worm gear 98 provided on the rotating shaft 96 of the DC motor 94 meshes with the worm wheel 100, the external input is transmitted from the worm wheel 100 to the rotating shaft 96 of the DC motor 94 via the worm gear 98. Is cut off. That is, the DC motor 94
Is restrained by the worm gear 98 and the worm wheel 100 in the inoperative state. For this reason,
When the DC motor 94 is not operating, the torque conversion mechanism section 42
The nut 44 of the screw is prevented from rotating, and the screw shaft 4
6 is also prevented from moving in the axial direction. Therefore, for example, when the vehicle is stopped, the DC motor 94 is stopped while the inner pad 14 and the outer pad 16 are kept in pressure contact with the disc rotor 18 to maintain the brake operating state (the parking brake operating state). be able to.

On the other hand, when the parking brake lever is operated while the DC motor 94 is inactive, the operation lever 52 is forcibly rotated via the operation rod 59.
Therefore, the screw shaft 46 connected to the operating lever 52 by the support shaft 54 is also forcibly rotated. Here, in the non-operating state of the DC motor 94, as described above, the nut 4 of the torque converting mechanism 42 is used.
4 is blocked from rotating, so screw shaft 4
When 6 is forcibly rotated, the screw shaft 46 itself rotates and moves along the axial direction to press the inner pad 14. As a result, the brake is activated. That is, by operating the operation lever 52,
The brake can be activated.

Therefore, for example, when the operation lever 52 is operated while the vehicle is stopped, the parking brake can be activated. Further, by operating the operation lever 52 when the DC motor 94 is not operating (when the vehicle is running), it can be used as an emergency brake.

As described above, in the disc brake device 90, not only the first brake system operated by the driving force of the DC motor 94 but also the operation lever 52 (support shaft 5
The second brake system operated by the rotation of 4) can be constructed in a single device. In addition, the worm wheel 100 is attached to the nut 44 of the torque conversion mechanism unit 42 which is composed of the ball screw 48 and converts the rotational force into the linear movement force.
, And the worm gear 98 provided on the rotating shaft 96 of the DC motor 94 is meshed with the worm wheel 100, so that the apparatus becomes compact as a whole.

As described above, in the disc brake device 90 according to the second embodiment, two different brake systems independent from each other can be formed in a single device while maintaining the reliable brake operation performance. Moreover, this can be realized with a simple structure and a small shape.

In each of the above embodiments, the operating rod 59 is connected to the operating lever 52, and the operating lever 52 (support shaft 54) is rotated by manual operation of the parking brake lever. However, the present invention is not limited to this. Alternatively, for example, a deceleration (acceleration) mechanism such as a gear may be provided between the operation lever 52 and the operation rod 59, and the manual operation force of the parking brake lever may be decelerated (accelerated) and transmitted. Further, the configuration is not limited to the configuration in which the operation lever 52 (support shaft 54) is simply rotated by a manual operation, but the configuration may be such that it is rotated by another drive source such as a motor.

Further, in each of the above-described embodiments, an example in which the present invention is applied to the so-called pin slide type (piston floating type) single cylinder type disc brake device 10 has been described, but the present invention is not limited to this. Other types can also be applied.

[0073]

As described above, according to the present invention, it is possible to construct two different brake systems independent of each other in a single device while maintaining a reliable brake actuation performance, and to implement this with a simple structure. It has an excellent effect that it can be realized with a small shape.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing the configuration of a disc brake device according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line 2-2 of FIG. 1 showing the configuration of an operation lever of the disc brake device according to the first embodiment of the present invention.

FIG. 3 is a sectional view showing a configuration of a disc brake device according to a second embodiment of the present invention.

FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. 3 showing the configuration of a worm gear and a worm wheel of a disc brake device according to a second embodiment of the present invention.

[Explanation of symbols]

 10 disc brake device 12 caliper housing 14 inner pad (brake pad) 16 outer pad (brake pad) 18 disc rotor 30 electric actuator 32 housing 34 cover 42 torque conversion mechanism part 44 nut 46 screw shaft 48 ball screw 50 support hole (forced moving means) ) 52 operation lever (forced movement means) 54 support shaft (forced movement means) 70 ultrasonic motor 72 stator 74 rotor 76 disc spring (biasing member) 90 disc brake device 92 electric actuator 94 DC motor 98 worm gear 100 worm wheel

Claims (4)

[Claims] 1. A disc brake device in which a brake pad is brought into pressure contact with a disc rotor to generate a braking force, and an electric motor that is immovable by an external input to a rotating portion, and a nut to which the electric motor is connected, A screw shaft assembled to the nut by a ball screw and provided so as to face the brake pad, converts the rotational force of the electric motor into an axial movement force of the screw shaft, and moves the screw shaft in the axial direction. A torque conversion mechanism section that presses the brake pad by force and a screw shaft of the torque conversion mechanism section are coupled, and the screw shaft is forcibly rotated and moved in the axial direction independently of the operation of the electric motor. A disk breaker characterized by having a means for forced movement. Apparatus. 2. The ultrasonic motor comprising: an electric motor; a rotor connected to the nut; a stator fixed to the housing so as to face the rotor; and an urging member for pressing the rotor into pressure contact with the stator. The disc brake device according to claim 1, wherein: 3. The torque conversion mechanism section includes a worm wheel connected to the nut, and a worm gear provided on the rotary shaft of the electric motor and meshed with the worm wheel. 1. The disc brake device according to 1. 4. The forcibly moving means is provided with a support hole provided in an axial center portion of the screw shaft, and a support shaft which is prevented from relative rotation and enters into the support hole so as to be relatively movable in the axial direction. The disc brake device according to claim 1, 2 or 3, wherein the disc brake device is formed of: