MXPA05000402A

MXPA05000402A - Tool.

Info

Publication number: MXPA05000402A
Application number: MXPA05000402A
Authority: MX
Inventors: Nicolas Huth
Original assignee: August Ruggeberg Gmbh & Co Kg
Priority date: 2004-01-10
Filing date: 2005-01-07
Publication date: 2005-07-12
Also published as: BRPI0500010A; US20050153640A1; AU2005200072A1; DE102004001546A1; ZA200410251B; CA2490460A1; CN1636676A; EP1552904A1

Abstract

In a tool comprising a supporting part and a disk-shaped working part for machining operation, the supporting part comprises a supporting face for the working part and a permanent magnet within the supporting face. The working part comprises a coupling member of ferromagnetic material which is movable into magnetically clinging connection with the permanent magnet upon application of a counterpart supporting face to the supporting face.

Description

TOOL Description of the invention The invention relates to a tool with a carrier piece and a disc-shaped workpiece for machining with chip removal. Tools of this type are known in multiple configurations, in which a carrier part or a base body are respectively joined to a work piece constituted by a wear part. Workpieces of this type are, for example, abrasive media on a seat base, polishing wheels and cleaning or felt discs consisting of napped needle with integrated abrasive means. The carrier part and the workpiece are generally rotationally actuated. In known embodiments, a coupling part with an internal thread, which is screwed onto a thread of a carrier part, is placed on the face opposite the working side. Normally the placement and removal of the workpiece from the carrier piece takes effort or requires a lot of time or can be done only with great care. This is especially heavy, since workpieces of this type have to be changed very often after a short time of use. Just in that case, the height of the stacking of the work pieces is very high, given that the piece of REF. : 161315 coupling with the internal thread necessarily presents an important height. From EP 1 007 282 Bl it is known to fix an abrasive medium in the form of a sheet in a magnetized support. In this regard, the abrasive means has a ferromagnetic metal sheet. This is not appropriate for tools of the type described above. Accordingly, the invention has the task of producing a tool of the common kind in such a way that the realization and separation of the connection between the work piece and the work piece can be carried out very quickly and easily.

This task is solved according to the invention by the features of claim 1. The essence of the invention is in the fact that the workpiece has a coupling piece, which is held on the carrier piece by magnetic forces. By the variant of claim 2, and especially the following embodiments according to claims 3 to 6 and 15 to 17, there is further provided a possibility of transmission of the torque in positive connection and a centering. Claims 12 to 14 reproduce that, on the one hand, a large-area connection is obtained which also has a tensile strength between the coupling part and permanent magnets and which, however, on the other hand does not have an important influence on the Stacking height of the work pieces by the coupling piece. The other subordinate claims reproduce advantageous embodiments. Other characteristics, advantages and details of the invention result from the following description of exemplary embodiments based on the figures. A plan view of the contact surface of a carrier part of a tool according to the invention is shown in FIG. 1, FIG. 2 shows the tool according to the invention in cross section in an exploded view, FIG. plant of the counter-contact surface of the workpiece of the tool, Fig. 4 a section through an exploded representation of a coupling part with a permanent magnet, Fig. 5 a plan view of the contact surface of a carrier part of another embodiment, Fig. 6 the tool according to the other embodiment in cross section in an exploded view and Fig. 7 a plan view of the counter-contact surface of the work piece of the other example realization.

The tool represented in the figures consists in its basic structure of a carrier part 1 in the form of a support plate and a workpiece 2. The carrier part 1 has a carrier casing 3 composed of an elastic plastic, which has a ring-shaped contact surface 5. On its opposite side to the contact surface 5, the carrier part 1 has a threaded bore located concentrically with respect to the central axis 6, in which a drive shaft 8 of a tool drive not shown by means of a corresponding one can be screwed in. external thread 9. In drives for tools of this type can be the so-called angular grinders or straight grinders. In the carrier housing 3, that is to say on the side of the contact surface 5, a fastening body 10 is located, in which the bore 7 is formed and which has a flat groove 11 concentric with respect to the axis 6 with a polygonal cross-section. In the present case, the slit 11 is formed by flanks 12 of an equiangular and equilateral polygon, for example, of a hexagon. At the points of intersection of two adjacent flanks 12, a cut-out 13 is provided respectively. In the groove 11, that is to say sunken with respect to the application surface 5, a permanent magnet 14 is located in the form of a flat circular disc and fixed in the fastening body 10, for example, by means of adhesion. The fastening body 10 is conveniently composed of a non-magnetizable material, although it can also be made of a ferromagnetic material or partially of a ferromagnetic material, for example in the form of a composite material. The workpiece 2 itself is also formed as a circular disk and has a countercontact surface 15, which, when the workpiece 2 is placed on the carrier part 1, comes into contact with the counter-contact surface 15. Workpiece 2 has approximately the diameter or perimeter of the carrier part 1. In the present case, the workpiece 2 is constituted by an abrasive means 16 on a seat base 17, the counter-contact surface 15 being formed by the opposite side to the abrasive means 16 of the seat base 17. The abrasive means 16 of this type on a seat base 17 are normally configured flexibly, ie elastically. In a concentric manner with respect to the central axis 18 of the workpiece 2, a coupling part 19 of a ferromagnetic material is fixed to the counter-contact surface 15. This has a polygonal shape, corresponding essentially to that of the slit 11, that is, in the present case it is an equilateral and equiangular hexagon, whose flanks 20, when placed in the slit 11, are arranged on the flanks 12 of the slit 11, whereby a rotation-resistant connection between the work piece 2 and the carrier piece 1 is produced. Since the coupling piece 19 is composed of a ferromagnetic material, it remains fixed in the slit 11 because of the magnetic attraction of the permanent magnet 14. The magnetic forces act in the direction of the axes 6, 18. Because the workpieces 2 of this type, such as for example abrasive means 16 on a seat base 17, or discs of polishing or cleaning discs are applied in an inclined manner with respect to the surface to be worked, the axes 6, 18 therefore not being in perpendicular position with respect to the surface to be worked, the work pieces 2 are curved in the work stop together with the elastic carrier casing 3, whereby forces are produced between the coupling part 19 and the magnet 14 which raise the coupling piece 19 of the magnet 14. The magnet 14 has to be strong enough to produce such forces. Therefore, it does not serve only to prevent the work piece 2 from falling off the carrier part 1. On the opposite side to the counter-contact surface 15, the coupling piece 19 has a flat centering flange 21 projecting in a circular shape, which is touched tangentially with the six flanks 20 of the coupling piece 19. When placing the work piece 2 on the carrier piece 1 it is first introduced this centering tab 21 in the slit 11, whereby centering is performed. Then the workpiece 2 can be rotated together with the coupling piece 19 until the flanks 20 coincide with the flanks 12 so that then the coupling piece 19 is placed against the permanent magnet 14 or else keeping a small gap close to it. of the same and the counter-contact surface 15 is placed against the contact surface 5. The rapid fixing system formed between the carrier part 1 and the work piece 2 therefore has three partial functions, that is, the axial fixation. of the workpiece 2 and its clamping during the work process in the carrier part 1 by the magnetic forces, the transmission of the torque in positive connection between the flanks 12 and 20 and the centering during the assembly by means of the centering flange 21 insertable between the flanks 12. For the ratio of the diameter D2 of the workpiece 2 in relation to the largest diameter Di9 of the coupling piece 19 is valid: 1 <1. D2 / Di9 = 10, the small value of this ratio being valid for diameters D2 of workpiece 2 especially small, for example, approximately 20 mm, while the large ratio for large values of D2 is valid, for example, in the margin of 200 mm or more. Regarding the diameter D2 that is presented in practice, it is valid: 20 mm = D2 = 250 mm. Although the described quick-clamping connection between the workpiece 2 and the carrier part 1 is first applied to workpieces with rotary drive, it can also be applied to workpieces which can be actuated primarily in a linear fashion, for example in the case of a workpiece. you love orbitals If in such a case only one coupling is present, the configuration described protects against unwanted twisting of the workpiece in relation to the carrier part. As is further to FIG. 4, for the ratio of the largest diameter D19 of the coupling piece 19 to the axial thickness of the coupling piece 19 is valid 5 < DX9 / di9 = 100 and preferably 10 = D19 / di9 = 30. As for the ratio of the largest diameter Di9 of the coupling piece 10 to the diameter D14 of the permanent magnet, it is valid: 1 <1. D19 / D14 = 2. From the above indications it can be deduced that the coupling piece 19 with respect to its diameter Di9 and its thickness di9 on the one hand and the diameter D2 of the work piece 2 on the other hand, is extraordinarily flat. The stacking height of the work pieces 2 as wearing and exchange parts will therefore only be insignificantly influenced by the coupling part. The exemplary embodiment according to FIGS. 5 to 7 differs from the embodiment described above only in certain details. Therefore the same reference signs will be used without further explanation for the same parts. If they are equal parts from the functional point of view, but of different pieces from the constructive point of view, the same reference signs will be applied, although with an apostrophe. Several permanent magnets 14 'are provided, in the specific case six, located in the clamping body 10' at the same angular distances around the threaded bore 7. The threaded bore 7 is open towards the contact surface 5. The groove 11 'is delimited by flanks 12', which form an approximately equilateral polygon, the different flanks 12 'being bent in the direction of the axis 6 and the joining points or points of intersection of the flanks 12' being formed., which have contact with each other, such as rounded corners 22. By adapting to the modified carrier part 1 ', the work piece 2' has a coupling part 19 ', whose flanks 20' running around, correspond in shape and size with the flanks 12 'of the groove 11', of so that by engaging the coupling piece 19 'in the slit 11', the flanks 20 'make contact with the flanks 12'. Also the flanks 20 'are joined together by rounded corners 23, adapted to the rounded corners 22. The flanks 12"of the slit 11 'are inclined towards each other in the direction opposite to the application surface 5 towards the interior of the fastening body 10' The flanks 20 'of the coupling piece 19' are inclined in the same way one towards the other, so that during the introduction of the coupling part 19 'in the groove 11' not only a positive connection is made resistant to the rotation, but also a centering with respect to the central axis 6. In the coupling piece 19 ' a hole 24 is formed which corresponds to the size and length of the threaded bore 7 so that, with the corresponding conditions of the drive machine, the drive shaft 8, represented in the first embodiment, if necessary, also can enter the interior of the tool Regarding the relationships of diameters and thickness ratios, the explanations regarding the first embodiment are valid, of course, instead of six permanent magnets 14 ', another number can also be provided, for example four permanent magnets. The contact surface 5 can be a continuous flat surface, but it can also be defined by a large number of ribs, not shown in detail, because in this case it has no relationship with this. It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects or products to which it refers.

Claims

CLAIMS Having described the invention as above, the content of the following claims is claimed as property: 1. Tool, characterized in that it is formed with a carrier piece, with a disk-shaped workpiece for machining with chip removal, and with a common central axis' presenting the carrier part with a contact surface for the workpiece and in the contact surface of at least one permanent magnet, the work piece presenting a counter-contact surface for the contact surface; and the workpiece presenting a coupling part of a ferromagnetic material, which can be brought to a magnetic clamping connection with the at least one permanent magnet, by contacting the counter-contact surface with the contact surface. Tool according to claim 1, characterized in that the at least one permanent magnet is located in a groove in the carrier part and the coupling piece enters the slot .. 3. Tool according to claim 2, characterized in that the groove has a non-round cross section and that the coupling part has a non-round cross section adapted to the cross section of the groove. 4. Tool according to claim 3, characterized in that the slit and the coupling part have a polygonal profile. Tool according to claim 4, characterized in that the slot and the coupling part have a cross-section in the form of an equilateral and equiangular polygon. Tool according to one of claims 2 to 5, characterized in that the coupling part has a circular centering flange adapted to the groove. Tool according to one of claims 1 to 6, characterized in that the carrier part has a carrier housing and a fastening body enclosed by it at least partially. Tool according to claim 7, characterized in that the carrier housing is made of plastic. 9. Tool according to claim 7 or 8, characterized in that the fastening body is made of metal. The tool according to one of claims 1 to 9, characterized in that the carrier part has a connection for a rotary drive. Tool according to one of claims 1 to 10, characterized in that the workpiece is formed as an abrasive medium on a seat base. Tool according to one of claims 1 to 11, in particular according to claim 8, characterized in that the carrier housing is composed of an elastically yielding material. 13. Tool according to one of claims 1 to 12, characterized in that the ratio of the largest diameter (Di9) of the coupling piece to its thickness (d19) is valid: 5 < D19 / di9 = 100. Tool according to one of claims 1 to 13, characterized in that the ratio of the largest diameter (D2) of the workpiece to the largest diameter (D19) of the coupling part is valid: 1 < D2 / D19 = 10. "15. Tool according to claim 4, characterized in that the slit and the coupling part have flanks bent inwards. 16. Tool according to claim 15, characterized in that flank edges adjacent to each other and flanks adjacent to each other of the coupling piece are joined to each other by rounded corners. 17. Tool according to claim 15, characterized in that the flanks of the groove are inclined towards each other from the contact surface to the carrier part. Tool according to one of claims 1 to 17, characterized in that several permanent magnets are arranged in the carrier part. 19. Tool according to claim 18, characterized in that the permanent magnets are arranged at equal angular distances and spaced from the central axis. 20. Tool according to claim 11, characterized in that the work piece is made flexible.