KR20020093411A - Method of manufacture brake di sc for cast material and therefore - Google Patents

Abstract

PURPOSE: A brake disk for a cast iron and a method for manufacturing the brake disk are provided to suppress the vibration of a brake drum or a wheel and the breakage of a disk by manufacturing a brake disk through casting and to prevent the fade by promptly discharging the frictional heat through plural holes formed in the disk. CONSTITUTION: A brake disk shape mold is formed by using 300-400 mesh of molding sand. A cast iron composite constituted of 3.12wt% of carbon, 0.74wt% of manganese, 2.04wt% of silicon, 0.10wt% of sulfur, 0.072wt% of phosphor, 0.16wt% of chromium, 0.18wt% of copper, and iron is molten in a melting pot or a cupola. The temperature of the molten material is 1300-1500deg.C. The molten material is put into the mold and cooled for 20-30 minutes. The surface of the cast brake disk is treated by post processing. Many holes(11) are formed in the brake disk(10).

Description

Brake disc for cast iron and its manufacturing method {Method of manufacture brake di sc for cast material and therefore}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cast iron brake disc and a method for manufacturing the same, and a brake disc for producing a brake disc using a casting method and a method for manufacturing the same.

In general, a brake disc is a part of a vehicle braking device, also called a brake rotor, which is bolted to a wheel hub of a vehicle, rotates with a wheel, and has a function of generating a braking force in contact with a brake laying ring.

As a material, aluminum alloy or steel plate is mainly used.In general, the brake disc has a fade phenomenon between the brake lid and the disc due to frictional heat of about 600 ~ 700 ℃, and the braking force is significantly lowered. Cooling fins or ribs are installed in the direction, or vent holes are provided between the two discs, which may serve to suppress temperature rise.

The brake disc 1 made of such aluminum or steel sheet is formed by welding a plurality of protrusions 5 formed on the surface of the disc 4 with each other under a state where the two discs 4 are opposed to each other. The plurality of ventilation holes 2 having a predetermined size are formed in the circumferential direction so that the brake disc 1 is completed.

However, as described above, the brake disc manufactured by the welding method between the disc and the disc has a long and continuous vehicle operation, and the welding portion 3 between the disc 4 shrinks and expands due to frictional heat between the disc and the lid. There is a problem that the disk shakes and shakes when the brake is dropped or deformed, and the surface of the disc is worn out.

The cause of the above problem is that the binding force of the welding protrusions 3 and 5 between the two discs 4 of the brake disc 1 is reduced by shrinkage expansion due to frictional heat to support the two discs 4. It is judged that the ability is caused by falling.

An object of the present invention is to provide a cast iron brake disk and a method for manufacturing the same as a sand casting method using a molding sand, which is devised to solve the problems of the brake disk manufactured by the mutual welding method.

1: A perspective view of a brake disc made of steel sheet.

2: An exploded perspective view of a brake dask made of steel sheet.

3 is a perspective view of a cast iron brake disc of the present inventors.

4 is a process chart of the present invention cast iron brake disk.

<Description of the symbols for the main parts of the drawings>

1, 10: brake discs 2, 13 vent holes

3: welded part 4, 12: disc

5, 14 projection 11: hole

Therefore, the present invention was invented to solve such problems, C 3.12% by weight, Mn 0.74% by weight, Si 2.04% by weight, S 0.10% by weight, P 0.072% by weight, Cr 0.16% by weight, Cu 0.18% by weight, The remainder is melted to about 1300 to 1500 ℃ in a crucible or molten iron in a cast iron material of Fe to inject the molten metal into a sand mold produced in the form of a brake disc to produce a cast iron brake disc.

In the mold manufacturing process, the molding sand of 300-400 mesh is formed into the mold of the brake disc 10 shape, and the mold can maintain a constant shape by mixing a binder such as a resin or an adhesive into the molding sand.

When the mold thus prepared is put into a heating furnace at about 300 to 500 ° C. and calcined for about 10 to 20 minutes, the mold is not lost or broken even when a molten metal at about 1500 ° C. is injected.

After the molten metal is injected into the mold, it is held for 20 to 30 minutes, and when the cooling is completed, the mold is dismantled, and after removing the found sand from the brake disk vent 13, the hole 11 and the surface 12, After the process, the cast iron brake disc 10 is completed.

The disassembled mold is recycled and reused as foundry sand.

The cast iron brake discs manufactured by this process have mechanical properties with surface hardness of about 187 to 215 and compressive strength of about 207 N / mm2, and cast iron structure of graphite type A 89% and C + D. It is made of high strength heat-resistant cast iron in the form of dispersed structure of 11% of E type.

The cast iron brake disc, which has undergone the post-treatment process, maintains a smooth surface without any micropores or irregularities.

Through such a process, a cast iron brake disc is manufactured, but cast iron brake discs in which a plurality of holes 11 having a diameter of 3 to 5 mm are formed in a circle in the disc of the brake disc can also be manufactured.

As described above, a brake disc having a plurality of holes 11 formed in a disc has a frictional heat of about 600 to 700 ° C. when the brake laying pad is squeezed on the disc, so that the friction heat is discharged to the outside through the vent through the hole. It has the effect of reducing its own temperature, so it does not show any fade when braking.

In addition, the protrusion 14 which maintains the disc and the disc at regular intervals is also integrally fixed between the disc 12, so that no cracking or falling off occurs even after repeated shrinkage expansion by frictional heat.

As described above, according to the present invention, the brake disc is manufactured using a cast iron material by a casting method, so that the vibration of the brake drum or wheel and the disk are not broken at all compared to the disc manufactured by the welding method. In addition, by forming a plurality of holes in the disk disc in a circular arrangement, the frictional heat is rapidly discharged to the outside through the vent when the brake is operated, so there is no fade phenomenon and the braking force is excellent.

Claims (2)

A brake disc-shaped mold was produced from a molding sand of about 300 to 400 meshes, 3.12 wt% C, 0.74 wt% Mn, 2.04 wt% Si, 0.10 wt% S, 0.072 wt% P, 0.16 wt% Cr, and 0.18 wt% Cu. %, The remainder is molten cast iron material in a crucible or molten iron furnace to make the molten metal temperature 1300-1500 ° C, The cast iron brake for manufacturing the cast iron brake disc 10 through a post-treatment process of injecting the molten metal into the foundry sand mold and holding it for about 20 to 30 minutes, then cooling and dismantling the mold to process the surface of the cast brake disc. Disc manufacturing method. A cast iron brake disc, characterized in that a plurality of holes (11) are formed in a circular arrangement on both sides of the disc (12) of the brake disc (10) at regular intervals.