JP7320193B2 - Water intrusion prevention structure for vehicle disc brakes - Google Patents

Description

The present disclosure relates to a water intrusion prevention structure for a vehicle disc brake.

Patent Document 1 discloses a drum brake for a vehicle in which brake shoes are accommodated in a back plate body so as to be expandable and retractable. A back plate structure for a drum brake is described in which water and dust are prevented from entering the drum brake by loosely fitting into the drum brake.

JP-A-2002-295544

In Patent Document 1, the structure of Patent Document 1 suppresses the ingress of water into the drum brake provided with the back plate for accommodating and holding the brake shoes. Intrusion of water or the like into the brake cannot be suppressed.

Accordingly, an object of the present disclosure is to prevent water from entering a disc brake that does not have a back plate.

To achieve the above object, a first aspect of the present invention is a water intrusion prevention structure for a vehicle disc brake, comprising a disc rotor and a dust shield. The disk rotor has a rotor portion that extends cylindrically toward one side in the axial direction from the outer peripheral edge of a disc-shaped rotor bottom plate that is attached to the axle, and a diameter of the end portion of the rotor tube portion on the one side in the axial direction. It integrally has a donut plate-shaped disk portion arranged on the direction outside. The dust shield has a plate-shaped outer diameter side shield portion that faces and approaches the disk portion from one side in the axial direction, and a cylindrical inner diameter side shield portion that protrudes from the outer diameter side shield portion to the other side in the axial direction. and fixed to the vehicle body side that supports the axle. The outer peripheral surface of the inner diameter side shield portion faces and approaches the inner peripheral surface of the rotor cylindrical portion from the radially inner side. The upper surface of the outer peripheral surface of the inner diameter side shield portion is inclined downward toward the outer diameter side shield portion on one side in the axial direction. The dust shield is composed of a shield inner on the inner peripheral side and a shield outer on the outer peripheral side. The shield inner includes an inner inner diameter portion fixed to the vehicle body, an inner outer diameter portion disposed radially outside the inner inner diameter portion and substantially orthogonal to the axial direction of the axle, and an inner outer diameter portion bent from the outer peripheral edge of the inner outer diameter portion. It is integrally formed with the inner diameter side shield portion extending to the other side in the axial direction. The shield outer is integrally formed with an outer inner diameter portion that overlaps and is fixed to the inner outer diameter portion from one side in the axial direction, and the outer diameter side shield portion that extends radially outward from the outer inner diameter portion.

In the above configuration, on one side in the axial direction of the disk portion, the radially outer shield portion restricts the intrusion of water from the radially outer side to the radially inner side to some extent. In addition, the flow path of water, which is not blocked by the outer shield portion and has entered between the disk portion and the outer shield portion from the radially outer side and directed radially inward, is not blocked by the rotor on the other side in the axial direction. The inner diameter side shield portion is provided in the inner diameter side shield portion, so that the water is prevented from entering the rotor portion by the inner diameter side shield portion. Infiltration can be suppressed. Therefore, even with a disc brake that does not have a back plate, it is possible to prevent water from entering the rotor.

In addition , in the above configuration, the upper surface of the outer peripheral surface of the inner diameter side shield portion is inclined downward toward one side in the axial direction (the side away from the rotor bottom plate portion). The water that has flowed downward and reached the inner diameter side shield portion is discharged to one side in the axial direction by the upper surface of the inner diameter side shield portion without flowing down to the other side in the axial direction (inside the rotor portion). Therefore, the function of preventing water intrusion into the rotor portion can be enhanced.

According to the present disclosure, it is possible to suppress water from entering a disc brake that does not have a back plate.

It is the front view which looked at the brake equipment concerning one embodiment of the present invention from the direction of an axis. FIG. 2 is an exploded perspective view of the brake device of FIG. 1; 2 is a side cross-sectional view of FIG. 1; FIG. (a) is a rear view of the dust shield, and (b) is a side view of the dust shield. FIG. 4 is an enlarged view of a main portion of FIG. 3;

An embodiment of the present invention will be described below with reference to the drawings. In the following description, the axial direction is the direction in which the axle 1 extends, with one axial side (left side in FIG. 2) being the inner side of the vehicle and the other axial side (right side in FIG. 2) being the outer side of the vehicle.

The brake device (disc brake) of the present embodiment is an electric parking brake device (EPB: Electric Parking Brake), and as shown in FIGS. and a disk rotor 4 attached to the axle 1 of the rotor so as to be integrally rotatable. The caliper 2 and the actuator 3 are unitized and attached to the vehicle body.

The disk rotor 4 includes a rotor portion 5 having a U-shaped cross section in which a rotor tubular portion 7 extends cylindrically toward the vehicle inner side from an outer peripheral edge portion of a disc-shaped rotor bottom plate portion 6 , and an end of the rotor tubular portion 7 on one side in the axial direction. It integrally has a doughnut plate-shaped disk portion 8 arranged radially outwardly of the portion. A disk-shaped disk fixing plate 9 is fixed to the end portion of the axle 1 on the outside of the vehicle. are placed on the rotor bottom plate portion 6 from the inside of the vehicle, and a plurality of (six in the illustrated example) hub bolts 10 fixed to the rotor bottom plate portion 6 and extending to the outside of the vehicle are inserted through the rotor bottom plate portion 6 and the wheel. The disk rotor 4 and the wheel are fixed to the axle 1 by screwing and tightening a wheel nut (not shown). The disk portion 8 forms a friction surface sandwiched by a pair of pads (not shown).

The caliper 2 is fastened and fixed to a knuckle portion 11 that is fixed to the vehicle body and rotatably supports the axle 1 with a plurality of (two in the illustrated example) bolts 12 (shown in FIG. 1). A cylinder portion (not shown) is provided in the caliper 2, and a piston (not shown) is slidably provided in the cylinder portion. When the driver depresses the brake pedal (not shown), the brake fluid is supplied to the cylinder, the piston moves relative to the cylinder, and the pair of pads supported by the caliper 2 are moved to the disk rotor 4 by the piston. They are pressed and frictionally engaged. Thus, the braking force generated by the driver's operation of the brake pedal is generated by the supply of the brake fluid.

The actuator 3 is provided with an electric motor (not shown) whose motor shaft rotates according to the operation of a parking brake switch (not shown) inside the vehicle, and a transmission mechanism (not shown) that transmits the rotation of the motor shaft to the piston. be done. When the driver operates the parking brake switch, the rotation of the electric motor is transmitted to the piston via the transmission mechanism, the piston moves with respect to the cylinder portion, and the pair of pads are pressed against the disc rotor 4 to create a frictional relationship. match. Thus, the braking force as the parking brake is generated by the electric motor. Therefore, the brake device of this embodiment does not include a brake shoe for applying a braking force as a parking brake and a back plate for supporting the brake shoe.

The disk rotor 4 is a ventilated disk in which a plurality of fins 13 are provided inside the disk portion 8, and a plurality of ventilation passages 14 penetrating from the inner peripheral side to the outer peripheral side are formed by the plurality of fins 13 ( 2, 3 and 5). The disk portion 8 that has generated heat due to the frictional engagement with the pad is cooled by the air flowing through the ventilation passage 14 .

As shown in FIGS. 1 to 4, a dust shield 15 is provided inside the disk rotor 4 to prevent liquids such as water and solids such as dust and foreign matter from entering the rotor portion 5 . The dust shield 15 is formed by welding or the like the inner peripheral edge of the outer shield 17 on the outer peripheral side to the outer peripheral edge of the shield inner 16 on the inner peripheral side. It should be noted that the dust shield 15 may be composed of one part or three or more parts instead of the two parts of the shield inner 16 and the shield outer 17 .

The shield inner 16 includes a rectangular plate-shaped inner inner diameter portion 18 substantially orthogonal to the axial direction of the axle 1 , an inner side plate portion 19 that bends from the outer peripheral edge of the inner inner diameter portion 18 and extends to the outside of the vehicle, and an inner side plate portion 19 . It integrally has an inner outer diameter portion 20 that bends from an edge on the vehicle outer side and extends radially outward, and an inner diameter side shield portion 21 that bends from the outer peripheral edge of the inner outer diameter portion 20 and extends to the vehicle outer side. The outer circumference of the inner outer diameter portion 20 is circular, and the inner diameter side shield portion 21 is cylindrical.

The axle 1 is inserted through an axle insertion hole 22 formed in the inner inner diameter portion 18, and the inner inner diameter portion 18 is fastened to the vehicle outer side of the knuckle portion 11 on the vehicle body side with a plurality of bolts 23 (three bolts in the illustrated example). It is fixed (see FIG. 2). The outer peripheral surface of the inner diameter side shield portion 21 has a reverse tapered shape that expands in diameter from the inner side of the vehicle toward the outer side of the vehicle. See Figure 5).

The shield outer 17 has a substantially C shape in which a part of the donut plate shape is notched as a space for arranging the caliper 2 and the actuator 3 (see FIG. 4A). An outer inner diameter portion 24 that overlaps and is fixed from the inside of the vehicle, a plate-like outer diameter side shield portion 25 that continuously extends radially outward from the outer inner diameter portion 24, and an outer edge of the outer diameter side shield portion 25 that extends from the vehicle. It integrally has an outer peripheral portion 26 that bends outward. The inner diameter side shield portion 21 protrudes outward from the vehicle from the radially inner end portion of the outer diameter side shield portion 25 . The radially outer shield portion 25 faces and approaches the disk portion 8 of the disk rotor 4 from the inside of the vehicle. 5).

In this way, the dust shield 15 covers from the inside of the vehicle substantially the entire area of the surface of the disk rotor 4 on the inside of the vehicle where the caliper 2 and the actuator 3 do not overlap. The dust shield 15 includes a plate-shaped outer diameter side shield portion 25 that faces and approaches the disk portion 8 from the inside of the vehicle, and a cylindrical inner diameter side shield portion 21 that protrudes from the outer diameter side shield portion 25 to the outside of the vehicle. and is fixed to the knuckle portion 11 on the vehicle body side. The outer peripheral surface of the inner diameter side shield portion 21 is opposed to and close to the inner peripheral surface of the rotor tubular portion 7 from the radially inner side, and the upper surface of the outer peripheral surface of the inner diameter side shield portion 21 extends downward (vertically downward) toward the inside of the vehicle. ).

According to the present embodiment, the intrusion of water from the radially outer side to the radially inner side of the disc portion 8 due to the flow down on the vehicle inner side surface of the disc portion 8 or the flow down in the air passage 14 is prevented by the outer diameter side shield portion. 25 and the outer peripheral portion 26 to some extent. 5, the space between the disk portion 8 and the outer shield portion 25 and the air passage 14 are not blocked by the outer shield portion 25 and the outer outer peripheral portion 26, and the air flow path 14 is radially outward. The flow path of the water that has infiltrated radially inward from the rotor portion includes a path toward the inside of the rotor portion 5 outside the vehicle (a path from the inside of the rotor cylinder portion 7 to the rotor bottom plate portion 6). Since the inner diameter side shield portion 21 is provided on the path leading to the inside of the rotor portion 5 , the inner diameter side shield portion 21 can suppress the entry of water into the rotor portion 5 . Therefore, even with a disc brake that does not have a back plate, it is possible to prevent water from entering the rotor portion 5 .

In addition, since the upper surface of the outer peripheral surface of the inner diameter side shield portion 21 is inclined downward toward the inside of the vehicle (opposite side of the rotor bottom plate portion 6), the space and ventilation between the disk portion 8 and the outer diameter side shield portion 25 are reduced. The water flowing down the path 14 and reaching the inner diameter side shield portion 21 is discharged to the inside of the vehicle without flowing down to the outside of the vehicle (the inside of the rotor portion 5). Therefore, the function of preventing water from entering the rotor portion 5 can be enhanced.

Although the present invention has been described above based on the above embodiments, the present invention is not limited to the contents of the above embodiments, and can be appropriately modified without departing from the scope of the present invention. In other words, all other embodiments, examples, operation techniques, etc. made by those skilled in the art based on this embodiment are naturally included in the scope of the present invention.

For example, in the above embodiments, an example of an electric parking brake device has been described, but the present invention can be applied to various other disc brakes. In the above-described embodiment, the inner diameter side shield portion 21 has a cylindrical shape whose outer peripheral surface expands toward the outside of the vehicle. It may have a cylindrical shape that slopes outward, or it may have a cylindrical shape in which the upper surface of the outer peripheral surface does not slope.

Further, in the above embodiment, the ventilated type disk rotor 4 in which the ventilation passage 14 is formed has been described, but the present invention is applied to a solid type disk rotor (solid disk) that does not have the ventilation passage 14. You may

INDUSTRIAL APPLICABILITY The present invention is widely applicable to vehicle disc brakes.

1: Axle 2: Caliper 3: Actuator 4: Disk rotor 5: Rotor portion 6: Rotor bottom plate portion 7: Rotor cylindrical portion 8: Disk portion 9: Disk fixing plate 10: Hub bolt 11: Knuckle portions 12, 23: Bolt 13: Fin 14: ventilation path 15: dust shield 16: shield inner 17: shield outer 18: inner inner diameter portion 19: inner side plate portion 20: inner outer diameter portion 21: inner diameter side shield portion 22: axle insertion hole 24: outer inner diameter portion 25 : Outer diameter side shield part 26: Outer peripheral part

Claims (1)

A rotor portion in which a rotor cylindrical portion cylindrically extends to one side in the axial direction from an outer peripheral edge portion of a disk -shaped rotor bottom plate portion attached to an axle; A disk rotor integrally having a donut plate-shaped disk portion arranged in the
It has a plate- shaped outer diameter side shield portion that faces and approaches the disk portion from one side in the axial direction, and a cylindrical inner diameter side shield portion that protrudes from the outer diameter side shield portion to the other side in the axial direction. , and a dust shield fixed to the vehicle body side that supports the axle,
an outer peripheral surface of the inner diameter side shield portion is opposed to and close to an inner peripheral surface of the rotor cylindrical portion from the radially inner side;
the upper surface of the outer peripheral surface of the inner diameter side shield portion is inclined downward toward the outer diameter side shield portion on one side in the axial direction;
The dust shield is composed of a shield inner on the inner peripheral side and a shield outer on the outer peripheral side,
The shield inner includes an inner inner diameter portion fixed to the vehicle body, an inner outer diameter portion disposed radially outside the inner inner diameter portion and substantially perpendicular to the axial direction of the axle, and the inner outer diameter portion. is integrally formed with the inner diameter side shield portion that bends from the outer peripheral edge of the and extends to the other side in the axial direction,
The shield outer is integrally formed with an outer inner diameter portion that overlaps and is fixed to the inner outer diameter portion from one side in the axial direction, and the outer diameter side shield portion that extends radially outward from the outer inner diameter portion. there is
A water intrusion prevention structure for a vehicle disc brake, characterized by:

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