JP7364211B2 - brake rotor - Google Patents

Description

TECHNICAL FIELD The present invention relates to a brake rotor.

As a brake rotor for a disc brake device, a plurality of grooves extending in a direction intersecting the direction of rotation of the sliding surface are formed on an annular sliding surface against which a brake pad (hereinafter also simply referred to as a pad) is pressed. Some are known (see, for example, Patent Document 1).

These brake rotor grooves are caused by a phenomenon in which the pad pressed against the sliding surface during braking becomes hot and gas generated from the pad resin gets interposed between the pad and the sliding surface, reducing the braking force. (fade phenomenon) and remove wear particles.

Utility Model Publication No. 58-129344

In conventional brake rotors, when the brake pad is pressed against the sliding surface of the rotating brake rotor, the outer circumferential side of the sliding surface tends to become hotter because the circumferential speed is faster than the inner circumferential side. There was a problem in that more gas was generated between the pad and the sliding surface on the outer peripheral side of the sliding surface, resulting in a reduction in braking force.

The present invention has been made to improve the above-mentioned current situation, and an object of the present invention is to provide a brake rotor that can suppress a decrease in braking force.

The present invention provides a brake rotor in which a plurality of grooves extending in a direction intersecting the rotational direction of the sliding surface are formed on an annular sliding surface on which a brake pad is pressed, and the grooves include: The sliding surface includes a plurality of inner grooves formed on the inner circumference side and a plurality of outer grooves formed on the outer circumference side, and the number of the outer grooves is greater than the number of the inner grooves. It is something.

According to the brake rotor of the present invention, since the number of outer grooves formed on the outer circumferential side of the sliding surface is greater than the number of inner grooves formed on the inner circumferential side, the brake pad is formed on the sliding surface. When the brake pad is pressed against the brake pad, gas and abrasion powder, which are generated more on the outer circumference side where the peripheral speed is faster than on the inner circumference side, can be efficiently removed from between the sliding surface and the brake pad, and a decrease in braking force can be suppressed.

By the way, in a disc brake device, a phenomenon in which high-frequency abnormal noise is generated during braking, so-called brake squeal, may occur. It is known that one of the causes of brake squeal is resonance of pads pressed against the sliding surface of the brake rotor. In order to prevent such brake squeal, it is sufficient to suppress the movement of the pad during braking.

Therefore, in the brake rotor of the present invention, an annular groove concentric with the center of rotation of the sliding surface is formed at a position between the inner groove and the outer groove of the sliding surface .

According to this aspect, as the pad is repeatedly pressed against the sliding surface, a shape corresponding to the annular groove of the sliding surface is formed on the friction surface of the pad (the surface that frictionally engages with the sliding surface). The protrusions are naturally formed. During braking, the protrusions on the friction surface of the pad fit into the annular grooves on the sliding surface of the rotor, so that the movement of the pad is restrained by the rotor, thereby suppressing brake squeal.

In such an aspect, the inner groove and the outer groove may be provided at a distance from the annular groove.

According to this aspect, since the ends of the inner circumferential groove and the outer circumferential groove are not continuous with the annular groove, it is possible to form an annular groove with no step on the inner wall surface, and the annular groove can be formed on the pad friction surface. Brake squeal can be suppressed by accurately forming protrusions with corresponding shapes. Further, it is possible to prevent gas and abrasion powder discharged from the inner groove and the outer groove from entering between the annular groove and the protrusion on the pad friction surface and inhibiting the formation of the protrusion.

The brake rotor of the present invention can suppress a decrease in braking force.

It is a figure showing one embodiment of a brake rotor, (A) is a front view, (B) is a top view, and (C) is a right view. It is a figure which shows the same brake rotor, (A) is a back view, (B) is a front view which shows the positional relationship with a brake pad and a fin. 2(A) is a sectional view taken along the line AA in FIG. 2(B), and FIG. 2(B) is an enlarged sectional view showing the vicinity of the sliding surface in FIG. 2(A) together with a brake pad. Another embodiment of the brake rotor is shown, with (A) being a front view and (B) being a rear view. Still another embodiment of the brake rotor is shown, with (A) being a front view and (B) being a rear view. Still another embodiment of the brake rotor is shown, with (A) being a front view and (B) being a rear view. Still another embodiment of the brake rotor is shown, with (A) being a front view and (B) being a rear view.

Embodiments embodying the present invention will be described below based on the drawings. FIG. 1 is a diagram showing one embodiment of a brake rotor, in which (A) is a front view, (B) is a top view, and (C) is a right side view. FIG. 2 is a diagram showing the same brake rotor, with (A) being a rear view and (B) being a front view showing the positional relationship with the brake pad and fins. 3(A) is a sectional view taken along the line AA in FIG. 2(B), and FIG. 3(B) is an enlarged sectional view showing the vicinity of the sliding surface in FIG. 3(A).

As shown in FIG. 1, the brake rotor 1 integrally includes a substantially cylindrical fixing part 2 fixed to a wheel hub (not shown) and an annular disc part 3 extending radially outward from the fixing part 2. We are prepared. Both the front and back surfaces of the disc portion 3 constitute annular sliding surfaces 4, 4 against which the brake pad 21 is pressed. The brake rotor 1 rotates together with wheels (not shown) in a rotational direction R1 or an opposite rotational direction R2.

The brake pad 21 is disposed within the brake caliper 20, which is fixed to a non-rotating member of the vehicle body, facing the sliding surfaces 4, 4 on the front and back sides of the disc portion 3. The brake caliper 20 includes a cylinder (not shown) that operates a brake pad 21, and presses the brake pad 21 against the front and back sliding surfaces 4, 4 of the disc portion 3 when brake fluid pressure is supplied to the cylinder. , suppresses the rotation of the brake rotor 1.

The brake rotor 1 is generally called a ventilated rotor, and the disc portion 3 is integrally formed with an outer disc 5, an inner disc 6, and a plurality of fins 7. The disks 5 and 6 are provided parallel to each other at intervals in the axle direction, and are connected to each other by a plurality of fins 7 interposed between the disks 5 and 6. These fins 7 are arranged at intervals in the circumferential direction of the disk portion 3, and cooling passages are radially formed between adjacent fins 7.

The surface of the outer disk 5 and the surface of the inner disk 6 become sliding surfaces 4, 4 against which the brake pad 21 is pressed. Since these sliding surfaces 4, 4 basically have the same configuration, they will be described below without distinguishing between them.

The sliding surface 4 of the brake rotor 1 has a plurality of inner grooves 8 formed on the inner circumferential side of the sliding surface 4 and a plurality of outer grooves 9 formed on the outer circumferential side of the sliding surface 4. ing. These grooves 8 and 9 are provided to extend in a direction intersecting the rotational directions R1 and R2 of the sliding surface 4. In this embodiment, the grooves 8 and 9 are inclined and formed in a curved shape so as to be positioned closer to the inner circumferential side as the grooves advance in the rotation direction R1. The length of the inner groove 8 is longer than the length of the outer groove 9.

The inner grooves 8 are arranged in an annular portion on the inner peripheral side of the sliding surface 4 at equal angular intervals in the rotational directions R1 and R2 of the brake rotor 1. In this embodiment, the eight inner grooves 8 are arranged with a phase difference of 45 degrees with the rotation center of the brake rotor 1 (the rotation center of the sliding surface 4) as the origin.

The outer grooves 9 are provided in an annular portion on the outer circumferential side of the sliding surface 4 in a larger number than the inner grooves 8, and are arranged at equal angular intervals in the rotational directions R1 and R2 of the brake rotor 1. In this embodiment, the twelve outer grooves 9 are arranged with a phase difference of 30 degrees with the rotation center of the brake rotor 1 as the origin.

As described above, the brake rotor 1 of the present embodiment has a plurality of grooves extending in a direction intersecting the rotational directions R1 and R2 of the sliding surface 4 in the annular sliding surface 4 against which the brake pad 21 is pressed. The grooves include a plurality of inner grooves 8 formed on the inner circumferential side of the sliding surface 4 and a plurality of outer grooves 9 formed on the outer circumferential side. The number of inner grooves 8 is greater than the number of inner grooves 8.

When the brake pad 21 is pressed against the sliding surface 4 of the rotating brake rotor 1, the outer peripheral side of the sliding surface 4 tends to become hotter because the peripheral speed is faster than the inner peripheral side, and the sliding surface Although more gas and wear particles are generated between the brake pad 21 and the sliding surface 4 on the outer peripheral side of the surface 4, the number of outer grooves 9 formed on the outer peripheral side of the sliding surface 4 is larger on the inner peripheral side. Since the number of inner grooves 8 is greater than the number of inner grooves 8 formed, gas and wear particles generated more on the outer circumferential side than on the inner circumferential side can be efficiently removed from between the sliding surface 4 and the brake pad 21. Decrease in braking force can be suppressed.

Furthermore, an annular groove 10 concentric with the center of rotation of the brake rotor 1 is formed in the sliding surface 4 of the brake rotor 1 at a position between the inner groove 8 and the outer groove 9. The outer groove 9 and the inner groove 8 are spaced apart from the annular groove 10. That is, the outer peripheral end of the inner groove 8 is not continuous with the annular groove 10, and the inner peripheral end of the outer groove 9 is not continuous with the annular groove 10.

In this way, the annular groove 10 that is concentric with the rotation center of the sliding surface 4 is formed between the inner groove 8 and the outer groove 9 of the sliding surface 4, so that the brake pad 21 can be slid on the sliding surface 4. As the braking action of pressing the brake pad 21 against the sliding surface 4 is repeated, a protrusion 21a having a shape corresponding to the annular groove 10 of the sliding surface 4 naturally forms on the friction surface of the brake pad 21 that frictionally engages with the sliding surface 4. It is formed. During braking, the projections 21a of the brake pad 21 fit into the annular grooves 10 of the sliding surface 4 of the brake rotor 1, so that the movement of the brake pad 21 is restrained by the brake rotor 1. Thereby, vibration (resonance) of the brake pad 21 pressed against the sliding surface 4 of the brake rotor 1 during braking can be suppressed, and brake squeal can be suppressed.

Further, since the inner groove 8 and the outer groove 9 are provided with a space between them and the annular groove 10, and the ends of the inner groove 8 and the outer groove 9 are not continuous with the annular groove 10, An annular groove 10 without steps can be formed. Thereby, the protrusion portion 21a having a shape corresponding to the annular groove 10 can be more accurately formed on the friction surface of the brake pad 21, and vibration of the brake pad 21 during braking and, by extension, brake squeal can be suppressed. Further, gas and wear particles discharged from the inner groove 8 and the outer groove 9 can be prevented from entering between the annular groove 10 and the protrusion 21a of the brake pad 21 and inhibiting the formation of the protrusion 21a. .

Note that the numbers of the inner grooves 8 and the outer grooves 9 are not limited to those in the embodiment described above, and any structure may be used as long as the number of outer grooves 9 is greater than the number of inner grooves 8. For example, as shown in FIG. 4, the number of outer grooves 9 may be increased with respect to the structure of FIG. 1, or as shown in FIG. 5, the number of inner grooves 8 may be reduced with respect to the structure of FIG. Good too.

Further, as shown in FIG. 6, the inner groove 8 and the outer groove 9 may be inclined in opposite directions with respect to the radial direction of the brake rotor 1. Further, the shapes of the inner groove 8 and the outer groove 9 are not particularly limited, and may be linear as shown in FIG. 7, for example. Further, the lengths of the inner groove 8 and the outer groove 9 are not particularly limited. For example, the inner groove 8 and the outer groove 9 may be formed to have the same length, or the outer groove 9 may be longer than the inner groove 8. It may also be formed for a long time.

Note that for each of the embodiments shown in FIGS. 4 to 7, the plan view and right side view are the same as the plan view and right side view shown in FIGS. 1(B) and (C). Further, for each of the embodiments shown in FIGS. 1 to 7, the bottom view is the same as the top view, and the left side view is the same as the right side view.

Furthermore, the plurality of inner grooves 8 formed on the inner circumferential side of the sliding surface 4 may have different shapes, or may have different inclination directions with respect to the radial direction of the brake rotor 1. It may also include things that are The same applies to the plurality of outer grooves 9 formed on the outer peripheral side of the sliding surface 4.

Furthermore, the groove widths and groove depths of the grooves 8, 9, and 10 may be the same or may be different from each other. Further, the cross-sectional shape of the grooves 8, 9, and 10 is not limited to the substantially U-shape as shown in FIG. 4, but may be substantially V-shape or rectangular.

Further, the number of annular grooves 10 concentric with the center of rotation of the sliding surface 4 may be two or more. Further, the outer circumferential end of the inner groove 8 may be connected (continuous) with the annular groove 10, and the inner circumferential end of the outer groove 9 may be connected to the annular groove 10. You can do it like this. Note that the position of the annular groove 10 in the radial direction of the brake rotor 1 is arbitrary. Further, the inner circumferential end of the inner groove 8 may be connected to the inner circumferential edge of the sliding surface 4, and the outer circumferential edge of the outer groove 9 may be connected to the outer circumferential edge of the sliding surface 4. (opening at the outer peripheral edge).

Further, although the brake rotor 1 of the above embodiment is of a ventilated type, the present invention is not particularly limited to this configuration, and for example, it is also possible to apply the present invention to a solid type brake rotor. .

The present invention is not limited to the above-described embodiments, but can be embodied in various aspects. The configuration of each part is not limited to the illustrated embodiment, and various changes can be made without departing from the spirit of the present invention.

1 Brake rotor 4 Sliding surface 8 Inner groove 9 Outer groove 10 Annular groove 21 Brake pad 21a Projections R1, R2 Rotation direction

Claims (2)

A brake rotor in which a plurality of grooves extending in a direction intersecting the rotating direction of the sliding surface are formed on an annular sliding surface against which a brake pad is pressed,
The grooves include a plurality of inner grooves formed on the inner circumferential side of the sliding surface and a plurality of outer grooves formed on the outer circumferential side,
The number of the outer grooves is greater than the number of the inner grooves, and
A brake rotor, wherein an annular groove concentric with a center of rotation of the sliding surface is formed at a position between the inner groove and the outer groove of the sliding surface. The brake rotor according to claim 1 , wherein the inner groove and the outer groove are spaced apart from the annular groove.

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