(19)
(11) EP 3 115 152 A2

(12) EUROPEAN PATENT APPLICATION

(43) Date of publication:
11.01.2017 Bulletin 2017/02

(21) Application number: 16178862.5

(22) Date of filing: 11.07.2016
(51) International Patent Classification (IPC): 
B24D 7/02(2006.01)
B24D 7/04(2006.01)
(84) Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR
Designated Extension States:
BA ME
Designated Validation States:
MA MD

(30) Priority: 09.07.2015 IT UB20151977

(71) Applicant: Mirani, Willem
37010 Cavaion Veronese (IT)

(72) Inventor:
  • Mirani, Willem
    37010 Cavaion Veronese (IT)

(74) Representative: Modiano, Micaela Nadia et al
Modiano & Partners Via Meravigli, 16
20123 Milano
20123 Milano (IT)

   


(54) ABRASIVE TOOL


(57) An abrasive tool (1) comprising a base body (2) that forms a portion (2b) for fixing to a movement device and intended to be rotated about a movement axis (100), the base body (2) being associable with a working body (3) that is extended around the movement axis (100) and is provided with at least one abrasive element (4); the base body (2) forms a coupling surface (2b) for the locking of the working body (3) and a lateral containment surface (5) that is intended to face at least one portion of the internal lateral surface (6) of the working body (3).




Description


[0001] The present invention relates to an abrasive tool for working elements made of stone-like, ceramic or similar material, even with high hardness.

[0002] Typically, abrasive tools are constituted by a metallic supporting body which is for example disk-shaped and has a working surface that supports the abrasive dust.

[0003] The supporting body is mounted on a machine tool, for example a buffing machine, which transmits to the tool a motion, typically a cyclic, linear, oscillatory or rotary motion, so as to move the working surface into contact with the part to be worked.

[0004] The tool can also be stationary, such as for example a lathe tool.

[0005] Known abrasive tools, by way of example pads, are constituted by a metallic supporting body, typically made of steel, which has a working surface coated with a layer of abrasive dust (for example diamond dust) mixed with a bonding substance, such as for example an adhesive.

[0006] However, although these constructive solutions are widely used, they are not free from drawbacks.

[0007] First of all, the use of bonding agents causes a lower efficiency of the abrasive capacity of the working surface.

[0008] Secondly, in order to ensure stable grip of the abrasive dust and of the bonding agent to the working surface, supporting bodies made of steel of considerable weight are often used: this causes an increase in the operating costs of the abrasive tool and in vibrations.

[0009] The aim of the present invention is to eliminate or at least reduce drastically the drawbacks described above.

[0010] Within this aim, an object of the invention is to provide an abrasive tool that is provided without using bonding agents or adhesives.

[0011] Another object of the invention is to provide an abrasive tool that is extremely light, so as to reduce operating costs and the risk of the onset of vibrations.

[0012] This aim, as well as these and other objects that will become better apparent hereinafter, are achieved by an abrasive tool according to the provisions of the appended claim 1.

[0013] Further characteristics and advantages of the invention will become better apparent from the description of some preferred but not exclusive embodiments of an abrasive tool according to the invention, illustrated by way of nonlimiting example in the following figures, wherein:

Figure 1 is a perspective view of an abrasive tool according to the invention;

Figure 2 is a diametrical sectional view of the tool of Figure 1;

Figure 3 is again a sectional view of a possible variation of the tool according to the invention.



[0014] The present invention relates to an abrasive tool, generally designated by the reference numeral 1.

[0015] The abrasive tool 1 comprises a base body 2, which forms a portion 2a for fixing to a movement device and is intended to be turned about a movement axis 100.

[0016] By way of example, the fixing portion 2a can comprise a flanged portion that is integral with the base body 2 to which a movement shaft is to be connected in a known manner.

[0017] The base body 2 can be associated with a working body 3 that is extended around the movement axis 100 and has at least one abrasive element 4.

[0018] Preferably, the working body 3 has a substantially annular shape.

[0019] According to the present invention, the base body 2 forms a coupling surface 2b for locking the working body 3 and a lateral containment surface 5 that is intended to face at least one portion of the internal lateral surface 6 of the working body 3.

[0020] Conveniently, the coupling surface 2b is extended on a plane that is substantially perpendicular to the movement axis 100.

[0021] Advantageously, the lateral containment surface 5 comprises a cylindrical surface that is extended around the movement axis 100.

[0022] Such cylindrical surface is extended at right angles to the coupling surface 2b.

[0023] Preferably, there is a gap between the lateral containment surface 5 and the internal lateral surface 6 of the working body 3.

[0024] With reference to the embodiment shown in the figures, the abrasive tool 1 is provided with means for the detachable fixing of the working body 3 to the coupling surface 2b.

[0025] By way of example, the detachable fixing means comprise a plurality of threaded elements 8 for connection between the base body 2 and the working body 3.

[0026] In order to facilitate centering and/or the transfer of torque from the base body 2 to the working body 3, axial connection pins are conveniently provided.

[0027] The base body 2 has, at the surface arranged toward the working body 3, a central portion 10a that is recessed with respect to the top 10b of the lateral containment surface 5.

[0028] Conveniently, there is a connecting surface between the top 10b of the lateral containment surface 5 and the recessed central portion 10a.

[0029] Such connecting surface comprises a curvilinear shape 11 and/or an inclined or step-like plane 12.

[0030] If, as shown in Figures 1 and 2, there is a curvilinear shape 11 of the connecting surface, it has been found that it is preferable for said curvilinear shape to have a concavity that is directed outward.

[0031] The abrasive element 4 is extended at a higher level than the top 10b of the lateral containment surface 5.

[0032] According to one practical embodiment, at least one insulating layer 7 is interposed between the working body 3 and the base body 2.

[0033] The base body 2 is made of metallic material and preferably of aluminum.

[0034] The abrasive element 4 is obtained for example by sintering abrasive dust with metallic bonding agent in order to obtain a so-called sintered grinding wheel.

[0035] The working body 3 is made advantageously of a metal or metal alloy which is optionally different from the one that provides the base body 2.

[0036] Conveniently, the working body 3 is made of steel.

[0037] Conveniently, the insulating layer 7 is made of polymeric material and in particular of silicone rubber.

[0038] As an alternative, the insulating layer 7 can comprise a lamina made of plastic or metal, for example copper.

[0039] The abrasive tool 1 according to the invention allows to eliminate any vibrations that cause unpleasant acoustic resonance and low reliability, significantly reducing consumption thanks to the aerodynamic shape that is determined by the lateral containment surface and by the connecting surface.

[0040] Furthermore, the presence of the lateral containment surface 5 allows to channel, during the rotation of the abrasive tool, a part of the air toward the abrasive element 4, limiting its overheating and increasing its life significantly.

[0041] In practice it has been found that the invention has achieved the intended aim and objects in all of the embodiments.

[0042] All the characteristics of the invention indicated above as advantageous, convenient or the like may also be omitted or be replaced with equivalents.

[0043] In practice, the materials used, so long as they are compatible with the specific use, as well as the shapes and dimensions, may be any according to requirements.

[0044] All the details may further be replaced with other technically equivalent elements.

[0045] The disclosures in Italian Patent Application no. 102015000032351 (UB2015A001977), from which this application claims priority, are incorporated herein by reference.

[0046] Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.


Claims

1. An abrasive tool (1) comprising a base body (2) that forms a portion (2b) for fixing to a movement device and intended to be rotated about a movement axis (100), said base body (2) being associable with a working body (3) that is extended around said movement axis (100) and is provided with at least one abrasive element (4), characterized in that said base body (2) forms a coupling surface (2b) for the locking of said working body (3) and a lateral containment surface (5) that is intended to face at least one portion of the internal lateral surface (6) of said working body (3).
 
2. The abrasive tool (1) according to claim 1, characterized in that said coupling surface (2b) is extended on a plane that is substantially perpendicular to said movement axis (100).
 
3. The abrasive tool (1) according to one or more of the preceding claims, characterized in that said lateral containment surface (5) comprises a cylindrical surface that is extended around said movement axis (100).
 
4. The abrasive tool (1) according to one or more of the preceding claims, characterized in that a gap is formed between said lateral containment surface (5) and said internal lateral surface (6) of said working body (3).
 
5. The abrasive tool (1) according to one or more of the preceding claims, characterized in that it comprises means for the detachable fixing of said working body (3) to said coupling surface (2b).
 
6. The abrasive tool (1) according to one or more of the preceding claims, characterized in that said detachable fixing means comprise a plurality of threaded elements (8) for connection between said base body (2) and said working body (3).
 
7. The abrasive tool (1) according to one or more of the preceding claims, characterized in that said base body (2) has, at the surface arranged on the side of said working body (3), a central portion (10a) that is recessed with respect to the top (10b) of the lateral containment surface (5).
 
8. The abrasive tool (1) according to one or more of the preceding claims, characterized in that it comprises a connecting surface between the top (10b) of said lateral containment surface (5) and said recessed central portion (10a).
 
9. The abrasive tool (1) according to one or more of the preceding claims, characterized in that said connecting surface comprises a curvilinear shape (11) and/or an inclined plane (12).
 
10. The abrasive tool (1) according to one or more of the preceding claims, characterized in that it comprises at least one insulating layer (7) between said working body (3) and said base body (2).
 




Drawing











Cited references

REFERENCES CITED IN THE DESCRIPTION



This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

Patent documents cited in the description