Soft polishing disc with holes and method of manufacturing the same

Abstract

A soft polishing disc with holes is composed of an abrasive member, which is obtained by radially disposing abrasive pieces each composed of a sand paper having abrasive grains coated on a soft base cloth while partially stacking the abrasive pieces and by coupling them with each other by a thermosetting resin, and ventilation holes are formed through the disc. The soft polishing disc with holes can stably grind and polish a workpiece even if it is soft or hard and has a good air ventilation property, maintains an air cooling effect for a long period of time, is difficult to be loaded with chips, increases the heat radiation property of an abrasive surface and makes it to difficult for a workpiece to be burnt.

Description

BACKGROUND OF THE INVENTION AND RELATED ART STATEMENT[0001] The present invention relates to a polishing disc and a method of manufacturing the same. More specifically, the present invention relates to an improved polishing disc that is used by being mounted on a rotary tool such as a grinder or the like to grind and polish a material of steel, non-ferrous metal, stone, wood, ceramics and the like and to a method of manufacturing the same.[0002] Disc type polishing grindstones are mounted on a grinding machine and rotated thereby to grind and to polish a workpiece composed of steel, non-ferrous metal, stone, wood, ceramics and the like, and used by being mounted on a rotary tool such as a grinder or the like. They are widely used in the various fields of industries such as building construction, shipbuilding, engineering works, electric works and the like.[0003] An offset type resinoid grindstone disc, for example, is exemplified as a technology of a conventional grinding and polish...

AI Technical Summary

Problems solved by technology

The offset type resinoid grindstone disc has bad heat radiation on the grinding surface thereof because it is inferior in air permeability in grinding.

Thus, the offset type resinoid grindstone disc has such a problem that burning is caused to a workpiece and that the ability of the disc is reduced because it wears by itself and is loaded with chips ground from the workpiece.

However, the flexible grindstone disc has a problem in that it is promptly worn and consumed and loading is caused thereto and that a workpiece is burnt due to the insufficient radiation of the disc while it is used.

Further, a material that can be polished and ground by the disc is limited only to steel, cast iron, and stainless steel.

Further, a sand paper type disc, which is constructed such that abrasive pieces each composed of a sand paper having abrasive grains coated on the surface thereof, are radially disposed while being partially stacked, has a similar problem.

However, exfoliated abrasive grains and the fiber pieces of the sand paper are sunk into the disc in a short period of time and the disc is loaded therewith, which reduces the ability of the disc as well as the air permeability thereof is deteriorated, and the workpiece is burned due to insufficient radiation.

A problem that is commonly arisen in these polishing discs resides in that since they are used by being rotated at a very high speed with respect to a workpiece, the workpiece is burnt by frictional heat of high temperature generated thereby.

A reason why this problem is arisen is that a large pressure is applied to the workpiece by the polishing disc when it is polished thereby.

However, since the synthetic rubber ordinarily has small pores, it is loaded with chips that are produced when the workpiece is polished and further it is exfoliated from a base sheet when it is rotated at a high speed because it is badly bonded thereto.

Thus, the synthetic rubber cannot be practically used for a long period of time.

However, while the polishing disc is not exfoliated from the base sheet when it is rotated at a high speed in a practical use, an effect of preventing the burning of a workpiece for a long period of time cannot be found because the recessed portions are collapsed and blocked due to the elasticity of the polishing disc.

Thus, it cannot be said that the polishing disc has a practically usable ability because an air cooling effect that is realized by the maintenance of air permeability is exhibited for a very short period of time.

Accordingly, the polishing disc cannot be effectively used.

Further, the disc has a problem that large noise and vibration are produced in polishing because the abrasive member 26 is hard.

Furthermore, while the disc is protected by a pad attached to the back surface thereof for safety, the pad is liable to be broken because the ventilation holes 28 have a large diameter, which prevents the abrasive member 26 from being used until it is perfectly consumed.

Thus, the disc is is ineffectively used and an operating cost is increased.

Hard workpieces are liable to be more burnt because they are heated to a high temperature, whereas soft workpieces are liable to cause loading on a disc because chips are produced therefrom in a large amount.

As described above, the conventional polishing discs have a problem that loading and burning are caused in a short period of time due to an insufficient cooling ability and the ability of the disc is reduced thereby and that loading and burning are further caused because the discs are heated to a high temperature due to insufficient radiation.

However, a nylon sheet that is melt by heat is not preferable.

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