EP0988133B1 - Grinding tool, specially for hand-held oscillating devices - Google Patents

Abstract

The tool body of the grinding tool consists of a holder for fixing the tool to the oscillating device and a flange of relatively soft, flexible material fixed thereto, supporting the abrasive paper and designed or arranged with axial dimensional flexibility at its outer edge. This results in the advantage that, in particular, increased pressure via the tool edge on the grinding surface is avoided. Very soft and very fine work can thus be carried out, so that when grinding or polishing, for example, an unsatisfactory new finish the defects can be perfectly eliminated by the grinding tool according to the invention and, under these circumstances, the peripheral edge of the tool does not act rigidly on the finish, leaving traces behind.

Description

The invention relates to a grinding tool for Hand-held oscillation devices according to the preamble of the claim 1 as e.g. for fine grinding, so for grinding of vehicle repainting is used.

As is well known, new paints are not always closed avoid that dirt particles fall into the fresh paint or other impurities and bumps as well Paint runs occur.

So far, has been used to correct these painting errors Tool used that is made of a cylindrical plastic block about 3 cm in diameter, on the underside flat sandpaper with the help of an adhesive strip is glued on. The processing is done by hand and is extremely tedious and very often unsatisfactory as a result.

Grinding tools are known, together with hand-held oscillation devices Find use (see e.g. the DE 94 10 754.8 A1 and the prospectus from Fein "Feinschleifer plus "8.96). These well-known grinding tools each have relatively stiff grinding plates, on their Underside of sanding sheets can be glued on. The whole Machining area of the tools is continuous equally firm or hard, up to the outer edge, so that a particularly sensitive, soft, touch-up regrinding and polishing is not carried out sufficiently optimally can be. In addition, these tools are on the respective Oscillating device rigid and in a predetermined, parallel work surface alignment arranged, causing problems in tight spaces can arise.

From US-A-4 523 411 is also a wet grinding tool known in which a bell-shaped housing as a holder or a rigid plate is provided on the end face a soft-elastic flange with a conical shape below extending outer surface is attached to the Active surface a sanding sheet can be attached. The flange has a large axial recess in the center Introduction of grinding fluid. The tool is over its holder rigidly attached to the oscillation device, so that Handling problems arise in inaccessible places can. You can also use this wet machining tool not in an inclined position, i.e. peripherally, precisely Repair work can be carried out, as appropriate Inclined position of the tool the centrally inserted Liquid flows out in an undesirably large amount. The taper of the flange only serves the more optimal Work in workpiece corners.

Finally, EP 141 139 A2 shows (FIGS. 4 to 7) Grinding tool according to the preamble of claim 1 with grinding dust suction, in which at the plate-shaped underside of a joint holder a cylindrical Flange is attached, which is essentially the has the same outer diameter as the holder disc. Here is a pivoting of the tool to the oscillator possible. Due to the lack of elasticity of the flange however, cannot do accurate paint touch-up work be performed.

The object of the invention is a grinding tool above Specify the type mentioned, by the very precise and fine grinding work, especially reworking of paint defects can be carried out optimally.

This task is accomplished by a generic grinding tool solved with the features of claim 1. In the subclaims advantageous configurations are specified.

Accordingly, the flange is made of soft material while the holder is cylindrical and at its the Flange-facing side set back in diameter is, e.g. due to an edge rounding, an edge bevel or a diameter gradation. The sandpaper bearing flange is axial at its outer edge Completely designed or arranged. This is given the particular advantage that in particular a higher Pressure across the tool edge on the grinding surface is avoided. So it can be worked very softly and very finely so that when grinding or polishing e.g. improper repainting, the defects perfectly eliminated by the grinding tool according to the invention and the tool circumferential edge not hard, leaving traces, worked into the paint.

The axial compliance of the flange is according to the invention thus achieved in that the support surface of the flange on the holder is much smaller than that Working surface of the flange. This is a protruding one Flange part available, which with axial edge pressure stress correspondingly elastic and soft is turned.

It is advantageous if the flange is known per se Way is made of soft rubber or soft plastic, while the holder is made of hard plastic. You can Bracket and flange e.g. be firmly glued together. It however, there is also the possibility of flange and holder e.g. removable with Velcro or adhesive tape to connect, which has the advantage of quick interchangeability if one of the two parts breaks or the Use of different flanges in connection with allows the same bracket, which is very inexpensive can impact.

It is particularly advantageous if the holder is also a joint is formed, forming a bearing block, which on his one end carries the flange and the other Side, preferably in a corresponding axial Recess, a via a pivot axis in the trestle carries a swivel-mounted swivel link (joint head), via which the tool is attached to the oscillation device takes place. So here is the advantage of an additional one Angle adjustability is given, i.e. the active, the surface of the tool carrying the sandpaper is im Relationship to the oscillation device in the angle or in its Adjustable inclination so that optimal handling with optimal working effect, even on narrow, difficult to access Worktops, is possible. Of course can instead of a simple joint with a single one A two-axis joint also known pivot axis be provided, the two pivot axes perpendicular stand to each other so that the inclination of the active tool surface can be designed arbitrarily, which is very advantageous in terms of handling and work result.

It is also advantageous if the holder at least is essentially cylindrical on the flange side and with its axis standing vertically on the flange is arranged and when it on the flange facing Side has very rounded edges or accordingly is rounded in diameter. This can be done by a Flange, which is arranged as a concentric to the holder cylindrical Disc is formed, with holder and Have flange essentially the same diameter can, in the peripheral zone of the active area a high axial compliance can be achieved. With something stronger axial pressure on the edge or the outer edge section, this outer flange part becomes axially elastic give way while its central part is firmly attached to the holder e.g. is glued. Depending on the size of the rounding, gradation or bevel diameter of the holder is also the Flexibility of the flange may be different.

In a further development, the flange in itself be known cone-shaped, with a cross-sectional taper pointing towards the holder, whereby the flange is apron-shaped to the outside or to the work surface expanding, protruding. This is through the additional cross-sectional taper a particularly high axial elasticity of the flange is present, so that a very precise, very soft machining is possible.

In a further advantageous embodiment, between The holder and flange are essentially cylindrical Support disc arranged, the diameter of which is larger than the outside diameter of the holder. By the relative large support disc, which is also made of the same material can be made like the holder, i.e. made of hard plastic, on the one hand, the holder can have any outer peripheral shape have, i.e. cylindrical, rectangular, square or polygonal. Also, what can be extremely beneficial is a polishing cover that looks like a pot hood is formed, pulled over the rubber flange and support disc with this polishing cover being a sheepskin can. With just a few movements of the hand, one can Grinding wheel, by covering the sheepskin hood, in transform a polishing disc with extremely good properties.

The large diameter of the support disc also represents a larger grinding or working surface of the Flange safe, which is particularly useful for machining larger, flat surfaces is a great advantage. Of course then has the support disc in diameter due to rounding, gradation or edge breakage smaller work surface or is simply a corresponding one smaller outside diameter of the disc in relation provided for the flange.

The support plate can either be in one piece with the Be formed holder, or support disc and holder are two separately manufactured parts, e.g. about axial guided screws or gluing firmly connected are removable or with adhesive strips or Velcro are interconnected. It can be done simultaneously in the releasable version of the soft flange on the support disc be releasably glued so that, in particular for storage of this grinding attachment only a holder is to be provided, to which, for. B. via Velcro, several flanges with different designs, with attached support disc, in different Forms and sizes can be assembled in modules can be put.

Of course, instead of the rotationally symmetrical Execution of the tool (cylindrical, conical) also one Polygonal version can be used. So z. B. the Holders have a square cross-section while the support disc (here then support plate) with flange e.g. can be designed triangular or hexagonal.

To minimize the flutter tendency of the tool is from Advantage if the position of the joint or the active working side of the tool is possible and in a known manner by a stiff Bearing construction, arrangement of locking screws or the provision of facilities such as locking balls or - bolt.

It is known that usually additional grinding Abrasives, polishes, water or soapy water be used. When using conventional tools are additional abrasives and coolants before or again and again, from separate containers onto the tool or to apply the surface to be processed. According to the invention is now possible by an axial through the tool body, for active Working surface opening feed line this machining additive if necessary continuously and directly to bring to the active site. By one with the respective Liquid-fillable bellows-like container that is connected to the grinding tool via a hose, the agent can be conveniently supplied. This can in particular more rational for larger areas to be processed be worked.

The container holding the additive liquid, the as bellows or simply elastic, balloon-shaped can be interchangeable or refillable be, i.e. the elastic container can be fixed be connected to the hose and by a closable Opening must be filled. However, it can also e.g. over a Connected screw connection with the hose and also in the manner of an already prepared or prepared filled cartridge can be replaced if necessary.

The arrangement of the container can also be done differently become. So the container can hang freely on one longer supply hose can be attached so that its. Actuation from the free hand during processing is noticeable. However, there is also the possibility the bellows via precautions known per se, such as clamps, to attach to the oscillation device so that the corresponding necessary pumping movements of one of the fingers of the the oscillating device carrying hand can. It is also conceivable that the bellows in the device housing formally incorporate or integrate that only a membrane-like pressure surface or only part of the container is visible.

The size of the grinding tool or grinding attachment varies according to the possible diameter sizes of the Sanding surfaces (2 to 19 cm in 1 cm steps). The used Sandpaper is usually round with a bent edge and provided with adhesive strips so that the grinding attachments can be equipped with it. The grain of the Sandpaper can range from very fine to coarse, accordingly the requirements vary.

The invention is described below using several exemplary embodiments explained in more detail with reference to the drawing.

Fig. 1:

eine perspektivische Ansicht auf ein erfindungsgemäßes Schleifwerkzeug in erster Ausführung, mit kleinem Konusflansch,

Fig. 2:

eine perspektivische Ansicht wie in Fig. 1, auf ein Schleifwerkzeug in zweiter Ausführung, mit großem Konusflansch und Abstützscheibe,

Fig. 3 bis 5:

drei Ansichten eines Schleifwerkzeuges in dritter Ausführung, mit zylindrischem Flansch und

Fig. 6:

eine perspektivische Ansicht auf ein Schleifwerkzeug gemäß Fig. 1, mit Behälter und Zuführschlauch für Zusatzmittel.

Show it:

Fig. 1:

1 shows a perspective view of an inventive grinding tool in the first embodiment, with a small conical flange,

Fig. 2:

1 shows a perspective view as in FIG. 1, on a grinding tool in the second embodiment, with a large conical flange and a support disk,

3 to 5:

three views of a grinding tool in the third version, with a cylindrical flange and

Fig. 6:

a perspective view of a grinding tool according to FIG. 1, with container and feed hose for additives.

The grinding tool shown in Fig. 1 consists of a cylindrical holder 1, on one, here lower End face, a conical flange 2 so attached is that its circumference is conical or apron-shaped downwards so expanded that an annular flange enlargement the width "d" is present. The holder face is also, as in connection with FIGS. 3 and 4 closer described, reset in diameter; e.g. by Rounding, grading or beveling. The free End face of the flange 2 is known per se Equipped with sanding paper 3 and interchangeable Adhesive strips or Velcro arrangements. So can, as is well known in grinding tools, this Sandpaper, also called flowers or cloverleaf, if necessary can be replaced easily and quickly. The Holder 1 is designed as a joint and has in it top, opposite the active work surface an axial slot 4 in which a flat joint head 5 via a radially guided in the holder Joint pivot axis 6 is pivotally arranged. The Rod end 5 is either directly on the output axis 7 an oscillation device attached or with the help a rod 7 in a known vibrating body holder (see DE 195 31 270 A1) attached, which in turn is firmly seated on the oscillator axis.

The embodiment shown in Fig. 2 has one Holder 1 on in the same way as that of the embodiment 1 is formed, namely as Joint. It has a cylindrical underside Support disc 8, which has a larger diameter than the holder 1 and at its lower end face Flange 2 made of soft material, such as soft rubber or plastic is attached. The flange-side edge of the support disc is also preferably rounded, such as 3 and 4.

In the further embodiment shown in FIGS. 3 to 5 is also cylindrical, as a joint trained holder 1 provided at its lower End face a strong rounding 9 of its front edge having. The flange 2 is in this embodiment formed as a cylindrical disc, the outer diameter is approximately equal to the outside diameter of the Bracket. Between bracket 1 and flange 2 is by the edge rounding 9 formed a gap 10, which is a retreat the peripheral zone of the width "d" of the flange 2 enables while working. Especially when on the lower flange edge is subjected to a working pressure, there is a possibility that this section "d" is pressed elastically into the gap 10, whereby a particularly sensitive work is possible. As in Fig. 4 is indicated with broken lines, instead of one Edge rounding also an edge bevel (left) or an edge gradation (right) can be provided to the To obtain distance "d" or a gap 10 that is sufficient axial deformability or elastic bendability allow the flange edge.

From Fig. 5 it can be seen how the joint slot 4 and the pivot axis are arranged in the holder 1.

In Fig. 6 it is shown how according to a tool 1 additionally a supply hose 11 is attached, the axially inserted into the holder in a not shown, axial feed line opening into the grinding surface or hole opens. The hose 11 supports at its other end a container 12, which is here in Art a bellows is axially pressure-elastic. The Connection between feed hose 11 and container 12 is realized here via a cap-shaped screw connection 12, this screw connection firmly attached to the hose while the container is holding a screw top bottle Is bellows body.

REFERENCE SIGN LIST

1.

holder

2nd

flange

3rd

Sandpaper

4th

slot

5.

Rod end (swivel link)

6.

Articulated swivel axis

7.

Output axis / rod

8th.

Support disc

9.

Rounding off

10th

gap

11.

Feed hose

12th

container

13.

Screw connection

Claims (15)

1. Sanding tool, for hand-held oscillating devices, with a tool body which can be fastened to the oscillating device and consists of a holder (1) in the form of a joint for pivotable fastening to the oscillating device and of a flange (2) which is made of flexible material and fastened coaxially to the latter and on the active side of which abrasive paper can be fastened in such a way that it can be changed, and which at its outer edge is embodied so that it projects beyond the supporting surface of the flange on the holder in an axially yielding form, characterised in that the flange is made of a soft material, and in that the holder (1) is cylindrical in shape and on its side facing the flange is reduced in diameter, e.g. by a rounded edge, a curved surface, a bevelled edge or a step in diameter.
2. Sanding tool according to claim 1, characterised in that the flange (2) is made of soft rubber or soft plastic and in that the holder (1) is made of hard plastic.
3. Sanding tool according to claims 1 and 2, characterised in that the holder (1) is essentially cylindrical in shape and in that the joint head swivelling member (5) of the holder joint is embodied as a flat eye with a swivel pin (6) passing through it, while the holder mounting assembly exhibits a slot-shaped recess (4) let in axially in the middle and through which the swivel pin (6) passes.
4. Sanding tool according to claim 1, characterised in that the holder (1) is essentially cylindrical in shape, at least on the flange side, and is arranged with its axis standing perpendicularly on the flange.
5. Sanding tool according to claims 1 to 4, characterised in that the flange (2) is embodied as a cylindrical disc and is arranged concentrically with the holder (1), and in that the holder (1) and the flange (2) essentially exhibit the same or different outside diameters.
6. Sanding tool according to claims 1 to 3, characterised in that the flange (2) is essentially the shape of a truncated pyramid, tapering in the direction of the holder.
7. Sanding tool according to claim 6, characterised in that between the holder (1) and the flange (2) there is a cylindrical supporting disc (8) the diameter of which is greater than the outside diameter of the holder (1) and at the same time equal in size to or smaller than the flange (2), the supporting disc (8) being either made in one piece with the holder (1) or connected detachably to the latter.
8. Sanding tool according to claim 1, characterised in that the holder (1) is embodied as a bi-axial joint the two swivelling axes of which are perpendicular to one another.
9. Sanding tool according to claim 3, characterised in that the joint can be immobilised in position steplessly or at a certain angle by means of arrangements known per se such as

   stiffness of the joint mountings,

   detent arrangements such as detent balls, pins or the like,

   immobilising screws which act directly on the moving parts, e.g. the pins.
10. Sanding tool according to claim 1, characterised in that a feeding line which opens towards the working surface is provided axially through the tool body (1, 2) to supply machining additives such as for example additional abrasive, polish, water, soap solution, and in that the feeding line is connected by means of a flexible feeding hose (11) to a container (12), the container (12)

    being exchangeable or refillable,

    formed overall with elastic walls or compressible axially like bellows for targeted and portioned delivery of the medium.
11. Sanding tool according to claim 10, characterised in that the container (12) can be fastened to the housing of the oscillating device within range of a corresponding operating finger, e.g. by means of a clamp.
12. Sanding tool according to claim 10, characterised in that the container (12) is connected to the tool body (1, 2) by means of a lengthy feeding hose (11) which allows operation by the free (second) hand not holding the oscillating device.
13. Sanding tool according to claims 10 to 12, characterised in that the container (12) is connected detachably to the hose (11) by means of a sealed quick-coupling, e.g. by means of a screw coupling (13).
14. Sanding tool according to claim 1, characterised in that a sanding or polishing covering which is made of sheep's wool or sheepskin for example and can be slipped like a cover over the flange (2) or over the supporting disc, is provided so that it can be fitted over the flange.
15. Sanding tool according to claims 1 to 10, characterised in that the abrasive paper (3) can be slipped over the edges of the soft flange (2) and is fastened to the flange (2) in a manner known per se by means of adhesive strips or hook and loop arrangements so that it can be changed.

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