BACKGROUND OF THE INVENTION

The invention relates to a sanding belt which comprises an elongate, thin, and flexible base part of woven material and coated with sanding particles secured with an adhesive. The sanding belt disclosed is of the type which is mounted as an endless belt around the periphery of a drive wheel or extended between several drive wheels or carrier wheels.

The known sanding belts have abrasive particles of silicium carbide (SiC) and aluminium oxide (A1 ₂ 0 ₃ ). These belts get worn quite quickly, which during operation results in increased power consumption and many operational stoppages in order for the belts to be changed. Moreover, due to the configuration and the production technique, the known belts can be used for sanding in only one direction.

The known belts develop considerable heat, for example when used for the sanding of articles of leather and synthetic materials. This leads to burn marks or the emission of undesired gases. Furthermore, sparks can arise if the articles contain hard components such as steel. Finally, the grinding dust generated by the known belts is a disadvantage, in that it forms a deposit between the abrasive particles and reduces the sanding ability of the belt.

EXPLANATION OF THE INVENTION

The characteristic feature of the belt according to the invention is that the abrasive particles consist mainly of

wolfram carbide (WC) . Wolfram carbide in particles can be bedded in a matrix of cobolt, which will typically comprise 5% of the particles.

The invention also relates to the use of sanding belts coated with abrasive particles of wolfram carbide for the sanding on non-metallic items.

Particles of thiε material get worn more slowly than particles of material hitherto used. When the sanding belt becomes unsharp and ineffective due to wear after sanding in one direction, the belt according to the invention can be turned for sanding in the opposite direction, in that the wear on the belt results in a sharpening of the particles' edges, which after turning of the sanding direction can engage with the item being sanded. Consequently, the belt according to the invention has a considerably longer lifetime than the known belts.

Only small amounts of grinding dust are created with particles of wolfram carbide, and therefore the belt's sanding abilities are better preserved than with the known belts.

The particles of wolfram carbide are sharper than the hitherto-used particles. Not so much force is required to press the article against the belt, and the same result can be achieved with a shorter sanding time than with the known belts used for non-metallic materials. These characteristics result in less heat generation and burn marks, and the development of undesired gases can be avoided. Finally, the power and energy required in the sanding processes are reduced.

Wolfram carbide is spark-free, which means that safety can

be increased in working environments where there are dangers of explosion and fire. The safety arrangements in these environments can therefore be simplified, with subsequent financial savings.

Since the particles of wolfram carbide are 60-70% heavier than the hitherto-used particles, the belt according to the invention is heavier per unit area. The result is that there are less vibrations when using the belt extended between several drive wheels and carrier wheels, and thus there is less noise during operation.

THE DRAWING

A preferred embodiment of the sanding belt according to the invention will now be described with reference to the only figure of the drawing, which shows a section through a part of a sanding belt.

DESCRIPTION OF THE PREFERRED EMBODIMENT

A preferred embodiment of the sanding belt according to the invention is made up of a woven base part 1, which is woven of cotton fibre. Other natural fibres or textile and synthetic fibres can also be used.

The woven material for use as the base part 1 is cut to the desired width and thereafter joined in a known manner, e.g. by splicing, to form an endless belt. The base part 1 is then coated with a layer of adherence primer 2 of the type Scotchcane TM Primer 4448.

Wolfram particles 5 of a suitable size are coated with a

metal primer to ensure better adhesion. The base part 1 is then given a layer of adhesive 3 of the type Peracit TM 5170 or 5191. As adhesive 3, other types of resin glue can be used. The particles 5 are applied to the adhesive 3 and, after hardening, the sanding belt is ready for use.

By this method of manufacture, the presence of adhesive over the abrasive particles 5 is avoided.