Field of the invention

The present invention relates to the field of the tools for sanding surfaces in particular to the holders used with the said tools.

Background of the invention

As is known, where it is necessary to sand surfaces to for example smooth or remove overlying layers of material (such as previous coats of paint, layers of dirt, etc. ), tools comprising an abrasive part are used.

Said abrasive part consists of a sheet of material (normally flexible) having a surface comprising abrasive material and is removably applied to a rigid body of any shape or size (said block) in the case of manual sanding or, in the case of mechanical sanders, said mechanical abrasive part is applied to a support (said pad) consisting of a body (normally disc-shaped) at the centre of which, perpendicularly thereto and on the opposite surface to the surface onto which the abrasive surface is affixed, a shaft is affixed that is capable of engaging with the corresponding guides of a rotary motor thus ensuring stability of the pad during the rotation imparted by the motor.

The abrasive part adheres to the support (block or pad as applicable) by means of suitable engagement means arranged on the surface of the pad opposite to the one that leads the shaft.

The engagement of the pad and the abrasive part must be such as to allow perfect adhesion during sanding but also an easy removal when the abrasive surface is worn and it is therefore necessary to remove it; said engagement is achieved with gripping materials, such as tear-off materials (such as Velcro© or other similar Hook and Loop pressure engagement materials).

Since, a considerable amount of dust clearly develops during sanding, in order to promote the extraction and elimination thereof the surface of the pad (and possibly also of the block) has a series of through and non-through holes that are variously arranged in the body of the pad (normally perpendicular to its two opposing surfaces).

Clearly the abrasive part also has the same holes that must be arranged at the level of the holes in the pad when it is applied to the pad. Prior to commencing work, the operator must therefore concern himself the correct positioning of the abrasive part on the pad, an operation that is at times complicated considering the high number of models on the market, which further vary on the basis of the materials to be processed, and on the number of existing holes, and that in any case restricts to the use of abrasive components that are complementary to the available pad that is used.

In view of the foregoing, the advantage of being able to use a pad that does not require the necessary presence of holes while in any case ensuring the extraction of sanding dust is clear.

Summary of the invention

The invention relates to a pad, or block, for the sanding of surfaces comprising engagement means consisting of transpirant tear-off material.

Brief description of the drawings

Fig. 1 (a - b) schematically represents two views of a pad according to the invention.

Fig. 2 represents a particular embodiment of a pad according to the invention. Detailed description of the invention

It has now been surprisingly found that by using transpirant tear-off products (such as Velcro ^® , also known as Hook and Loop materials) available on the market as engagement means of the pad and the abrasive parts to tear it is possible to overcome the aforementioned disadvantages by producing pads and blocks with which it an effective sanding can be performed with elimination of the respective dust even without the requirement to use different types of pads depending on the abrasive parts used as indicated in the state of the art.

In particular, according to the invention tear-off materials having a knitted surface structure with a thickness between 1 and 2 mm, preferably 1 mm and a weight between 300 and 400 g/m2, preferably 340 g/m2, are used.

Particularly preferred are the tear-off materials wherein the connecting elements are mushroom-shaped or hook-and-loop shaped like in traditional velcro. One example of material according to the invention is the PRESSOGRIP - FUNGO©. According to the invention, the tear-off material is applied to the surface of the pad (with or without holes) with a binding means that does not create any type of film or obstruction to the passage of air.

The application can therefore be performed, for example, using polyurethane, neoprene and acrylic binders or by means of ultrasonic welding or other similar methods.

It is possible to better exploit the transpirant characteristics intrinsic to the engagement materials with these applications and to therefore allow elimination of the dust that form during sanding, even without the need for the through holes present in the pads or blocks of the prior art.

The standard known and marketed abrasives will then be applied to the pads. As schematically shown in Figure 1 , the pad 10 according to the invention therefore presents the body 1 , possibly equipped with holes 2, whose engagement surface with the abrasive part is completely covered by a transpirant 3 tear-off engagement means.

According to a particular embodiment of the invention (see Figure 2) the surface of the pad or block onto which the transpirant engagement means as above described is applied has a series of channels produced along all or part of the surface; said channels 4 can of course be produced with any design or form (concentric circles, concentric centres connected by rays, spiral, regular or irregular geometric figures, etc.) and, if preferred, even the traditional holes 2. The use of the pads or blocks according to the invention is clearly identical to the traditional ones with holes, but, in this case, the need to match up the holes of the abrasive part with those of the pad is clearly eliminated making its use much more practical and, above all, universal, while ensuring a greater extraction and improved cleaning of the dust.