WO2007045960A1

WO2007045960A1 - Abrasive cutting disc and abrasive cutting element hereto

Info

Publication number: WO2007045960A1
Application number: PCT/IB2006/002882
Authority: WO
Inventors: Paul Christian BÖGLE
Original assignee: Heger Gmbh European Diamond Tools
Priority date: 2005-10-19
Filing date: 2006-10-16
Publication date: 2007-04-26
Also published as: DE602006020751D1; DE202005016385U1; EP1937440B1; EP1937440A1

Abstract

An abrasive cutoff wheel comprising a central disk (2) and a plurality of sintered abrasive segments (6) that are undetachably affixed to the outer circumference (8, 30) of the central disk (2) and that bilaterally protrude beyond the central disk (2) wherein the sintered abrasive segments (6) are fitted with a plurality of nubs (20) which project from the sides of the abrasive segments (6) and which are integrally molded and sintered with the abrasive segments (6) .

Description

ABRASIVE CUTTING DISC AND ABRASIVE CUTTING ELEMENT HERETO

BACKGROUND

The present invention relates to an abrasive cutoff wheel and abrasive segments for abrasive cutoff wheels.

Abrasive cutoff wheels of this kind are known for instance from the German patent documents DE C2 44 24 093 and DE A1 199 08 037.

SUMMARY

Illustratively the present invention offers the following advantages: Very quiet operation when cutting; higher cutting speeds by reducing the cutting surface at the cutting element; improved water feed when wet-cutting because of the abrasive segments' nubby structures; imparting a precutting effect to the cut edge of the workpiece sectioned by the abrasive cutting wheel.

Abrasive cutting wheels of the present invention are especially well suited to cut stone, in particular hard natural stone such as granite, masonry and concrete for instance of buildings, bridges and roads, for instance concrete walls, tile walls, concrete or tile ceilings, bridge components and road coverings made of concrete and of similarly hard materials.

BRIEF DESCRIPTION OF DRAWINGS

The present invention is elucidated below by means of an illustrative and preferred embodiment mode and in relation to the appended drawings.

Fig. 1 is a sideview of an abrasive cutoff wheel in accordance with an embodiment of the invention, Fig. 2 is an enlarged sideview of an abrasive segment of the abrasive cutoff wheel of Fig. 1 ,

Fig. 3 is a cross-section along the plane Ill-Ill of Fig. 2,

Fig. 4 is an enlarged cutaway from Fig. 3, and

Fig. 5 is a cross-section of an abrasive segment such as shown in Fig. 2 affixed to a cross-sectional portion of a central disk of the abrasive cutoff wheel of Fig. 1.

DETAILED DESCRIPTION OF EMBODIMENTS

The abrasive cutting wheel shown in Fig. 1 comprises a central disk 2 having a central aperture 4 to affix it to a rotary shaft and a plurality of sintered abrasive segments 6 undetachably affixed to the outer circumference 8 of the central disk 2. As shown in Fig. 5, the abrasive segments 6 project bilaterally by their sides 10 and 12 beyond the central disk 2. The sides 10 and 12 of the abrasive segments 6 are farther apart from each other than are the large sides 14 and 16 of the central disk 2. Therefore the central disk 2 is thinner than the abrasive segments 6. The central disk 2 is thinner at least at its rim than the abrasive segments 6.

The nubs 20 are mutually offset in the direction of cutting (circumferential disk direction) and in the direction of the height of the abrasive segments 6 (radial cutoff wheel direction) from one another on both the sides 10 and 12 of the abrasive segment 6 in a manner that, as seen in the direction of abrasion, they seem to be at least mutually adjoining or mutually overlapping. This feature is shown in particular in Figs. 1 and 2. Referred to the direction of rotation 24 of the abrasive cutoff wheel, the abrasive segments 6 each comprise a narrow front side 22 and a narrow rear side 24. Furthermore, each abrasive segment 6 comprises a narrow external surface 26 pointing away from the outer circumference 8 of the central disk 2 and a narrow inner surface 28 pointing toward the outer circumference 8 of the central disk 2. Each abrasive segment 6 is undetachably affixed at its narrow inner surface 28 to an external circumferential sector 30 of the outer circumference 8 of the central disk 2, for instance by soldering, welding, bonding or laser processing (laser beam welding).

The outer circumference 8 of the central disk 2 may be continuous (uninterrupted) or it may comprises circumferential notches 32. In the latter case the outer circumference of the central disk 2 is divided into affixation stubs 34 of which the narrow radially outer surfaces each constitute one of said external circumferential sectors 30 shown in Fig. 1.

The abrasive segments 6 are made of a sintered block of which the nubs 20 project from the segment sides 10 and 12, said nubs having been integrally molded and sintered with the abrasive segments. The abrasive segments together with their nubs 20 can be manufactured by sintering a mixture of powders containing the particles required for grinding, in particular diamond particles and preferably also metal powder(s). Following sintering, the abrasive segments 6 are undetachably affixed to the circumference 8 (30) of the central disk 2.

The nubs 20 preferably are cross-sectionally circular as shown in the sideviews of Figs. 1 and 2. However, other cross-sectional shapes may also be used.

Claims

1. An abrasive cutoff wheel comprising a central disk (2) and a plurality of sintered abrasive segments (6) that are undetachably affixed to the outer circumference (8; 30) of the central disk (2) and that bilaterally protrude beyond the central disk (2) wherein the sintered abrasive segments (6) are fitted with a plurality of nubs (20) which project from the sides (10, 12) of the abrasive segments (6) and which are integrally molded and sintered with the abrasive segments (6).

2. Abrasive cutoff wheel as claimed in claim 1 , wherein the outer circumference (8) of the central disk (2) is divided by a plurality of circumferential notches (32) into a plurality of affixation stubs (34) and the abrasive segments (6) each are affixed to one of said affixation stubs (34).

3. Abrasive cutoff wheel as claimed in one of the above claims, wherein the abrasive segments (6) contain diamond particles sintered into them.

4. Abrasive cutoff wheel as claimed in one of the above claims, wherein the abrasive segments (6) contain metal particles sintered into them.

5. Abrasive segments (6) for abrasive cutoff wheels, said segments comprising faces (10, 12) projecting bilaterally beyond the outer circumference of a central disk of said cutoff wheel after they have been affixed to said disk, the abrasive segments each being in the form of a sintered block, wherein the abrasive segments (6) each are fitted with a plurality of nubs (20) which project from the faces (10, 12) and which are integrally molded and sintered with the said segments (6).

6. Abrasive segments as claimed in claim 5, containing diamond particles.

7. Abrasive segments as claimed in either of claims 5 and 6, containing metal powder.