WO2008098626A1

WO2008098626A1 - Circular blade for working wood or other materials

Info

Publication number: WO2008098626A1
Application number: PCT/EP2007/057832
Authority: WO
Inventors: Gianpaolo Pozzo
Original assignee: Casals Herramientas Electricas S.L.
Priority date: 2007-02-16
Filing date: 2007-07-30
Publication date: 2008-08-21
Also published as: ITUD20070033A1; CN201154502Y

Abstract

Circular blade (10) for working wood or other materials, comprising a substantially flat disk-shaped body (12), and having a central zone, possibly provided with a hole (15), a peripheral zone (14) in which a plurality of cutting elements (13) are disposed in order to perform the work, and an annular intermediate zone, disposed between the central zone and the peripheral zone (14), in which one or more shaped through notches (17) are made. The width (L) of each notch (17) is greater than, or equal to, 1.0 mm and not more than 3.0 mm.

Description

"CIRCULAR BLADE FOR WORKING WOOD OR OTHER MATERIALS"

* * * * *

FIELD OF THE INVENTION

The present invention concerns a circular blade or saw, for making mechanical workings on wood or wood substitutes, such as for example chip board, MDF, plywood or other materials, such as plastic or metal materials, both ferrous and non-ferrous.

BACKGROUND OF THE INVENTION

Circular blades are known, for cutting wood or other materials, each consisting of a flat, disk-shaped steel body, which comprises a plurality of cutting elements, fixed in proximity with its external circular crown, commonly called teeth. The latter are usually made of hard metal (HW) and are able to make the cut by removing chip from the object to be cut or engraved.

During the use of a mechanical object, such as a circular blade or saw, subject to rotation, it has been recognized, from experience in industries that work wood and other materials, that the area of contact and the vibrations generated between the mechanical object and the piece being worked must be kept to a minimum.

Keeping the vibrations to a minimum helps to improve the finishing quality of the piece being worked, and at the same time the sound pressure generated is reduced.

In order to reduce these vibrations to a minimum, it is known to make a series of shaped through notches in an intermediate zone of the flat body of the circular blade, which are shaped for example like a coil or in a zigzag. The notches are able both to absorb or reduce the vibrations, and also to make the circular blade silent during use.

It is also known that in order to increase the capacity of absorbing the vibrations, and make the blade even more silent during use, inside the shaped notches a sound-proofing material is disposed, that is, a plastic or rubber material, with vibration absorbing characteristics. An innovative method for optimizing the deposition of sound-proofing material inside said shaped notches is described in the application for an industrial invention UD2007A000030 which Applicant filed on 13.02.2007. The anti-vibration notches on circular blades produced until now have a nominal width of less than 0.3 mm. In particular, in the Italian patent IT-B- 1.262.130 it is provided that the width is less than a millimeter, advantageously less than 0.5 mm and preferably 0.3 mm.

Known notches, due to their limited width, have the disadvantage, however, that they make it difficult to insert the sound-proofing material. Moreover, since the quantity of sound-proofing material inserted into the notches is relatively small, the anti-vibration and sound-proofing effect is relatively low.

One purpose of the present invention is to produce a circular blade in which, during use, the vibrations, and in particular the harmonic vibrations, are almost eliminated, with a consequent improvement in the quality of the cut and the life of the blade.

Another purpose of the present invention is to produce a circular blade in which, during use, the sound pressure generated by the rotation of the blade is at least greatly reduced, if not totally eliminated. The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.

SUMMARY OF THE INVENTION

The present invention is set forth and characterized in the independent claim, while the dependent claims describe other characteristics of the invention or variants to the main inventive idea.

A circular blade for working wood or other materials according to the present invention comprises a substantially flat, disk-shaped body, having a central zone, possibly provided with a hole, a peripheral zone in which a plurality of cutting elements are disposed in order to carry out the working, and an annular intermediate zone, disposed between the central zone and the peripheral zone, in which one or more shaped through notches are made.

In accordance with the above purposes, the width of each of said notches is greater than or equal to 1.0 mm and not more than 3.0 mm. Advantageously, said width is comprised between 1.0 mm and 2.0 mm.

From experiments made by Applicant, it has been found that the notches according to the present invention allow to accommodate inside them a greater quantity of sound-proofing material, which is injected inside the blade body. Moreover, a more complete filling of the notches has been found, compared with known solutions, where the nominal width of the notches is less than a millimeter.

Notches with a width comprised between one and three millimeters, in fact, accommodate a greater quantity of plastic material, which produces a greater effect of deadening the vibrations, which lowers the value of sound pressure during the cutting step.

In the circular blade according to the present invention the level of sound pressure is significantly lower than that of blades with the usual notches, from 0.2 mm to 0.3 millimeters wide.

In this way, the circular blade according to the present invention has a longer duration and allows to obtain a gentler cutting action. The life of the blade is increased due to the reduction in the harmonic frequency transported in the material. During the cutting action, the blade transfers energy to the piece being worked, which causes the blade to lose its state of balance.

Once the circular blade leaves its normal state of motion, unwanted harmonic frequencies are created, which are, however, deadened by the shaped notches, thanks to their increased width and the increased quantity of sound-proofing material inserted therein. The lower vibration value not only extends the life of the blade, but also increases the quality of the cutting finish produced.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other characteristics of the present invention will become apparent from the following description of a preferential form of embodiment, given as a non-restrictive example with reference to the attached drawings wherein: - fig. 1 is a lateral view of a circular blade according to the present invention; - fig. 2 is a section from II to II of fig. 1.

DETAILED DESCRIPTION OF A PREFERENTIAL FORM OF

EMBODIMENT

With reference to fig. 1, a circular blade 10 for working wood or other materials according to the present invention comprises a flat body 12, substantially disk-shaped, and a plurality of cutting platelets 13, disposed on a peripheral zone 14 of the flat body 12, and able to effect the cut when the flat body 12 is made to rotate with a determinate cutting speed. The flat body 12 is made of steel and comprises an axial hole 15 to allow the tool 10 to be associated with a mandrel, of a known type and not shown in the drawings, and a plurality of through notches 17, substantially coil shaped, angularly offset with respect to each other, made in an annular intermediate zone between the peripheral zone 14 and the axial hole 15, and able to absorb the vibrations which are generated during normal cutting operations, and hence to make the cut more precise and silent.

According to a characteristic feature of the present invention, the width L (fig. 2) of each of the notches 17 is greater than or equal to 1.0 mm and not more than 3.0 mm. Advantageously the width L is comprised between 1.0 mm and 2.0 mm. The notches 17 are filled with filling material 20 with a sound-proofing function, for example of the polymer type, which is disposed inside the through notches 17 in such a manner as to fill them completely and to effect a further absorption of the vibrations produced during normal cutting operations. The notches 17 are advantageously made using laser technology.

It is clear that modifications and/or additions of parts may be made to the circular blade 10 as described heretofore, without departing from the field and scope of the present invention.

For example, it comes within the field of the present invention to provide that the through notches 17 have a rectilinear, curved, undulating or other shape with respect to the coil shape shown in fig. 1.

It is also clear that, although the present invention has been described with reference to a specific example, a person of skill in the art shall certainly be able to achieve many other equivalent forms of circular blade for working wood or other materials, having the characteristics as set forth in the following claims and hence all coming within the field of protection defined thereby.

Claims

1. Circular blade for working wood or other materials, comprising a substantially flat disk-shaped body (12), and having a central zone, possibly provided with a hole (15), a peripheral zone (14) in which a plurality of cutting elements (13) are disposed, in order to perform the work, and an annular intermediate zone, disposed between said central zone and said peripheral zone (14), in which one or more shaped through notches (17) are made, characterized in that the width (L) of each of said notches (17) is greater than, or equal to, 1.0 mm and not more than 3.0 mm.

2. Circular blade as in claim 1, characterized in that said width (L) is comprised between 1.0 mm and 2.0 mm.

3. Circular blade as in claim 1 or 2, characterized in that said notches (17) are filled with a sound-proofing material (20) of polymeric type.

4. Circular blade as in any claim hereinbefore, characterized in that said notches (17) are made using laser technology.