JPH1113794A - Ventilated disc - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve cooling performance of an inner disc and an outer disc in the ventilated disc of a brake device for vehicle provided with rectilinear ribs and chevron-shaped forked ribs, by providing rectilinear intermediate ribs extending in the radial direction on the uniform positions in the circumferential direction between the rectilinear ribs. SOLUTION: The respective outer diameter of an inner disc 1 and an outer disc 2 are formed into the same size, but the inner diameter dimension is formed larger than the inner diameter dimension of the outer disc 2. Between these discs 1, 2, rectilinear ribs 3a... extending in the radial direction, chevron-shaped forked ribs 3b... across the radius line passing through the rectilinear ribs 3a... are formed so as to enlarge the space from the inner end side toward the outer end side, and in addition to them, intermediate ribs 3c... interposed on the uniform positions in the circumferential direction between the rectilinear ribs 3a... and extending in the radial direction are provided on a ventilated disc. Hereby accompanying rotation of the ventilated disc, both discs 1, 2 can be uniformly cooled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ventilated disc for a vehicle brake device.

[0002]

2. Description of the Related Art As a conventional ventilated disc, there is one disclosed in Japanese Utility Model Laid-Open No. 2-21342, in which the inner and outer discs are made of a smooth annular member, and the sliding surface of the inner disc is used. Are formed to be smaller than the area of the sliding surface of the outer disk, and linear ribs extending in the radial direction from the inner peripheral side to the central part of the two disks and are disposed on the outer peripheral side of the two disks. And an octagonal bifurcated rib formed symmetrically across a radius line passing through the linear rib, wherein both the disks are connected by the linear and bifurcated ribs, A large number of ventilation holes are provided by ribs.

[0003]

A conventional ventilated disc is required to rotate when the ventilated disc rotates.
After blowing new air with a larger flow rate than the inside opening of the ventilation hole into the ventilation hole due to centrifugal force, it is discharged into the atmosphere from the outside opening of the ventilation hole. There is a problem that it is insufficient. Therefore,
The present invention has been made to solve such a problem, and improves the conventional ventilated disc to improve the cooling performance of the disc portion between the adjacent linear ribs, thereby making the inner and outer discs uniform. The task is to cool.

[0004]

According to the first aspect of the present invention,
The area of the sliding surface of the inner disk is formed to be smaller than the area of the sliding surface of the outer disk, and the linear ribs extending radially from the inner peripheral side toward the center of the two disks and the linear ribs of the two disks In a ventilated disc having an eight-shaped bifurcated rib which is arranged on the outer peripheral side and is formed symmetrically with respect to a radial line passing through the linear rib, circumferentially uniform positions between the linear ribs A linear intermediate rib extending in the radial direction is interposed. According to a second aspect of the present invention, in the ventilated disk according to the first aspect, the average value of the graphite length is 220 μm.
FC15 having an attenuation capacity of 10.0 × 10 ⁻³ (Q ⁻¹ ) or more and a thermal diffusivity of 0.14 cm ² / sec or more.
It is characterized by being formed from flake graphite cast iron equivalent to zero.

[0005] Since the present invention is configured as described above, a large amount of air is sucked into the vent hole from the inner opening of the vent hole regardless of the rotation direction of the disk, and is forcedly blown along the ribs. The air is sequentially discharged into the atmosphere from the outer opening of the ventilation hole, and the inner disk and the outer disk are uniformly cooled, particularly through the intermediate rib.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The intermediate rib may extend linearly in the radial direction of the disk, and the cross section of the intermediate rib parallel to the inner and outer disks may be square. , May be elliptical.

The ventilated disc of the present invention is preferably formed from flaky graphite cast iron equivalent to FC150,
The following are used: The chemical components are in weight%
C: 3.55 to 3.70%, Si: 1.8 to 2.2%,
Mn: 0.5-1.2%, P: 0.4% or less, S: 0.
15% or less, Fe: substantial balance, carbon equivalent: 4.4% or less, and as impurities Cr: 0.1% or less, Cu:
0.2% or less, Mo: 0.1% or less, preferably 0.0
2% or less, Sn: 0.03% or less, Sb: 0.05% or less can be appropriately selected.

The base structure has a pearlite area ratio of 95% or more, an average graphite length of 220 to 290 μm, and a tensile strength of 150 MPa or more, preferably 175M.
Pa or more, more preferably about 210 MPa.
In order to obtain a damping capacity of 10.0 × 10 ⁻³ (Q ⁻¹ ) or more and a thermal diffusivity of 0.14 cm ² / sec or more, particularly, FC15
0 equivalent flake graphite cast iron, average graphite length 220μ
m or more are preferable.

The attenuation capacity is 10.0 × 10 ⁻³ (Q ⁻¹ ) or more, preferably 12 × 10 ⁻³ (Q ⁻¹ ), and more preferably 14 × 10 ⁻³ (Q ⁻¹ ).
× 10 ⁻³ (Q ⁻¹ ) or more. Thermal diffusivity is 0.1
4cm ² / sec or more, 1000-4 during brake braking
It is possible to reduce brake vibration caused by squealing at 000 Hz and uneven wear at high temperatures.

[0010]

1 and 2 show a ventilated disc according to the present invention. The ventilated disc according to the present invention is connected to inner peripheral edges of annular inner and outer discs 1 and 2, linear ribs 3a, forked ribs 3b and outer discs 2. FIG. The bottomed cylindrical hat portion 4 is formed in the same manner as the above-described ventilated disc of the related art, and has intermediate ribs 3c interposed at equal positions in the circumferential direction between the linear ribs 3a.

Next, the ventilated disk of the present invention will be described in detail. Although the outer diameters of the inner disk 1 and the outer disk 2 are formed to be the same,
The inner diameter of the inner disk 1 is formed larger than the inner diameter of the outer disk 2, and the area of the sliding surface 1 a of the inner disk 1 is formed smaller than the area of the sliding surface 2 a of the outer disk 2.

The ribs are provided on a straight rib 3a extending radially from the inner peripheral side of the inner and outer disks 1 and 2 toward the center, and on the outer peripheral side of both the disks 1 and 2, and An eight-shaped bifurcated rib 3b formed so that the interval increases from the inner end side to the outer end side with a radial line passing through the linear rib 3a interposed therebetween, and a uniform position in the circumferential direction between the linear rib 3a. An intermediate rib 3c is interposed and extends in the radial direction. A ventilation hole 5a is formed between the adjacent linear ribs 3a and the forked ribs 3b, and a ventilation hole 5b is formed between the opposed forked ribs 3b. Are formed, and a passage 6 is formed between the straight rib 3a and the forked rib 3b. The ventilation holes 5a and 5b communicate with each other via the passage 6.

The inner openings 7a of the ventilation holes 5a are respectively formed between opposing inner edges of the adjacent linear ribs 3a,
The outer openings 7b and 7c are formed between opposing outer edges of the adjacent bifurcated rib 3b and between opposing outer edges of the opposing bifurcated rib 3b, respectively. Although the area is larger than the area, the area of each of the outer openings 7b and 7c is smaller than the area of the inner opening 7a.

The ventilated disc of this embodiment is
It is formed from flaky graphite cast iron equivalent to FC150, and has a chemical composition of 3.55% C, 2.15% Si, M
n: 0.63%, P: 0.032%, S: 0.088
%, Fe: substantial balance, carbon equivalent: 4.27%, tensile strength is 193 MPa, average graphite length is 258 μm, damping capacity is 13.9 × 10 ⁻³ (Q ⁻¹ ), and thermal diffusivity is 0.
152 cm ² / sec.

FIG. 1 shows a ventilated disc of the present invention.
, A large amount of air flows into the ventilation hole 5a from the inner opening 7a of the ventilation hole 5a due to centrifugal force, and is blown along the straight rib 3a and the intermediate rib 3c and passes through the passage 6 It also flows between the forked ribs 3b, and then flows out into the atmosphere sequentially from the outer openings 7b, 7c, so that the two disks 1, 2 are uniformly cooled. Also,
The intermediate rib 3c improves the rigidity of the ventilated disc, and generates a large braking force.

The ventilated disc of the present invention has the same effect as described above even when rotated in the direction opposite to the above-described direction.

[0017]

According to the ventilated disc of the first aspect, the inner disc and the outer disc are uniformly cooled, so that the ventilated disc can be used regardless of whether the vehicle is moving forward or backward. It has a good cooling effect at any position and further increases the rigidity of the ventilated disc, so that each ventilated disc mounted on the vehicle always generates the same braking braking force and is stable The obtained braking effect is obtained. According to the ventilated disc of the second aspect, the ventilated disc of the first aspect is formed from flaky graphite cast iron equivalent to FC150, the average value of the graphite length is 220 μm or more, and the attenuation capacity is 10. 0x
Since it is 10 ⁻³ (Q ⁻¹ ) or more and the thermal diffusivity is 0.14 cm ² / sec or more, the thermal diffusivity becomes good, and no heat spot is generated on the braking surface, so that a better cooling effect is obtained.

[Brief description of the drawings]

FIG. 1 is a fragmentary front view of a main part of a ventilated disc according to the present invention.

FIG. 2 shows the ventilated disc II-II of FIG.
It is sectional drawing.

[Explanation of symbols]

 Reference Signs List 1 inner disk 2 outer disk 3a linear rib 3b forked rib 3c intermediate rib

Claims (2)

[Claims] The sliding surface of the inner disk is formed to be smaller than the sliding surface of the outer disk.
A linear rib extending radially from the inner peripheral side toward the center of the both disks and a linear rib disposed on the outer peripheral side of both disks and formed in contrast to a radial line passing through the linear rib. A ventilated disc provided with a forked bifurcated rib in the form of a circle, wherein a linear intermediate rib extending in the radial direction is interposed at a uniform circumferential position between the linear ribs. Ted disc. 2. The ventilated disc according to claim 1, wherein the average value of the graphite length is 220 μm or more, and
0.0 × 10 ⁻³ (Q ⁻¹ ) or more, thermal diffusivity of 0.14 c
m ventilated disc, characterized in that formed from the corresponding flake graphite cast iron FC150 having more than 2 ^/ sec.