JPH0430435Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a ventilated brake rotor, and more particularly to a ventilated brake rotor in which two rows of ventilation holes are formed inside a thick wall on the outer peripheral side of the rotor.

<Prior Art> As vehicles become more sophisticated, disc brake devices are increasingly used in which friction pads are pressed against an annular friction plate that rotates with the axle.

As a brake rotor used in this brake device, a so-called ventilated brake rotor is known in which ventilation holes are provided radially inside the thickness of a friction plate in order to increase heat dissipation efficiency. Compared to a solid brake rotor, where only its outer surface is in contact with the atmosphere, a ventilated brake rotor, which is hollow with ventilation holes, can radiate heat from the inside, making it extremely expensive. A cooling effect can be obtained.

On the other hand, in order to improve the performance of such ventilated brake rotors, for example,
As disclosed in Japanese Patent No. 80535, a structure in which two rows of ventilation holes are provided in the axial direction of the brake rotor has been proposed. According to this structure, it is possible to equalize the heat capacity of the sliding surface of the brake rotor with the friction pad on both sides, so that further improvement in braking performance can be expected.

By the way, as mentioned above, in the brake rotor provided with two rows of ventilation holes, the connection part (throat part) between the central cylindrical body connected to the axle and the annular plate provided with the friction plate on which the friction pad slides is Since the cooling air inlet is located at an intermediate position in the thickness direction of the annular plate, the cooling air inlet is opened along the entire circumference of both the inner and outer surfaces along the connecting portion between the central cylinder and the annular plate.

<Problems to be solved by the invention> However, in order to provide two rows of ventilation holes, the brake rotor is forced to increase the thickness of its outer periphery, which causes the concentration of thermal stress on the above-mentioned connection parts during casting. This inevitably led to the problem that control of casting quality became extremely difficult.

It is possible to deal with such problems by increasing the wall thickness of the connection part or by taking extra machining allowance to account for casting distortion, but this is not desirable as it increases weight and manufacturing costs. That's not the point.

In view of these problems in the prior art, the main purpose of the present invention is to provide an improved ventilated brake that ensures cooling efficiency with two rows of ventilation holes and does not reduce productivity. The purpose is to provide a rotor.

<Means for Solving the Problems> According to the present invention, the present invention has an annular shape extending radially outward from an open end located inside the vehicle body of a central cylindrical body having a mounting portion for the axle. 1 which are arranged opposite to each other with a gap between them via a large number of ribs arranged radially on both sides of the plate.
A ventilated brake rotor having a pair of friction plates, wherein a plurality of bridge portions are provided between an inner circumferential edge of one of the friction plates located on the outside of the vehicle body and an outer circumferential surface of the central cylindrical body. This is accomplished by providing a ventilated brake rotor characterized by:

<Operation> In this way, the inner circumferential edge of the friction plate and the outer circumferential surface of the central cylinder are partially connected, so stress concentration at the connection between the annular plate and the central cylinder is alleviated, and the casting Distortion can be reduced. Moreover, a sufficient air flow path can be secured in the gaps between the bridge parts.

<Embodiments> The present invention will now be described in detail with reference to specific embodiments with reference to the accompanying drawings.

FIGS. 1 and 2 show a brake rotor constructed according to the present invention. This brake rotor 1 has a central cylindrical shape with a bottom and a bottom 2 that is fixed to the axle. 3, and an annular portion 4 provided radially outward from the open end of the central cylindrical body 3, and the annular portion 4 is formed by directly connecting the entire circumference to the end edge of the central cylindrical body 3. an annular plate 5 that is in direct sliding contact with a friction pad (not shown);
A pair of friction plates 6a, 6b arranged on both the front and back sides of
It is made up of.

The annular plate 5 and the friction plates 6a, 6b are connected via a large number of ribs 7 arranged radially, thereby creating a well-known hollow space between the annular plate 5 and the friction plates 6a, 6b. Ventilation holes 8 are formed in the same manner as in the brake rotor.

The ribs 7 are alternately arranged on the front and back sides of the annular plate 5 in the circumferential direction.

The inner peripheral edge 9 of one friction plate 6a located on the outside of the vehicle body, which faces the outer peripheral surface of the central cylinder 3, and the outer peripheral surface 10 of the central cylinder 3 are equally spaced in the circumferential direction. They are connected by a plurality of bridge sections 11 arranged therein. The axial dimension of this bridging portion 11 is
A gap 12 is formed around the entire circumference between the opposing surfaces of the annular plate 5 and the bridge portion 11, and is equal to the thickness of one friction plate 6a. Therefore, the outside air flowing in from the gap 13 between the adjacent bridge parts 11 and the inner circumferential edge 9 of the friction plate can equally flow into each ventilation hole 8 .

A communication hole 14 is formed near the connection portion of the central cylinder 3 with the annular plate 5 so as to align with each ventilation hole 8 formed between each rib 7 . This is to prevent deterioration of the sand removal properties during casting due to the provision of the bridging portion 11. At the same time, the ventilation holes on the one friction plate 6a side are provided with the central cylinder 3. Ventilation can be obtained from both the inner and outer peripheries.

Generally, an annular portion having two rows of ventilation holes is open over the entire circumference between the inner circumferential edge of the friction plate on the outside of the vehicle body and the outer circumferential surface of the central cylindrical body. Therefore, the strength of the connecting portion between the central cylindrical body and the annular plate tends to be insufficient, and the surface of the friction plate tends to run out due to casting distortion or the like.

Therefore, according to the present invention, one of the friction plates 6a is partially connected to the central cylindrical body 3 by the bridging portion 11, which makes it possible to increase the strength of the same portion, thereby eliminating the above-mentioned disadvantages. This can be avoided.

<Effects of the invention> As described above, according to the invention, it is possible to improve the accuracy of brake rotor casting without affecting ventilation performance, which has a great effect on simplifying the manufacturing process and reducing costs. There is.

[Brief explanation of the drawing]

FIG. 1 is a partially cut-away front view of a brake rotor constructed according to the present invention.
FIG. 2 is a sectional view taken along the center line of the brake rotor. DESCRIPTION OF SYMBOLS 1... Brake rotor, 2... Bottom, 3... Central cylinder, 4... Annular part, 5... Annular plate, 6a, 6
b...friction plate, 7...rib, 8...ventilation hole, 9...
... Inner peripheral edge, 10 ... Outer peripheral surface, 11 ... Bridge portion, 1
2, 13...Void, 14...Communication hole.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) An annular plate disposed radially outward from an open end located inside the vehicle body of a central cylindrical body having a mounting portion for the axle and extending outward in the radial direction. A ventilated brake rotor having a pair of friction plates facing each other with a gap interposed therebetween, the inner circumferential edge of the friction plate located on the outside of the vehicle body and the friction plate located on the outside of the vehicle body. A ventilated brake rotor characterized in that a plurality of bridge portions are provided between the central cylindrical body and the outer peripheral surface thereof. (2) A utility model registration characterized in that a communication hole communicating between the inner peripheral side of the central cylinder and the gap is provided in a portion of the central cylinder corresponding to the gap between the ribs. A ventilated brake rotor according to claim 1.