EP2552646B1 - Holding body for flexible grinding means, and grinding system - Google Patents

Description

State of the art

The present invention relates to a holding body for a flexible abrasive, in particular a grinding pad, and a grinding system with such a holding body and a flexible abrasive.

Generic holding body in the form of sanding discs are for example in the DE 20 2009 000 880 , the EP 0 781 629 A1 and in the closest prior art, the DE 203 11 900 U1 described. These sanding pads have a soft support body, which may comprise, for example, foam, as well as a Velcro or adhesive layer for bonding with a flexible abrasive. The flexible abrasive may be, for example, a grinding wheel. These known sanding plates have a plurality of bores running in the axial direction, through which air and grinding dust produced during sanding can be sucked off. These holes penetrate both the soft layer and the Velcro or adhesive layer. Due to the necessary holes results for the respective grinding plate a characteristic hole pattern to which the abrasive used hereby must be adapted. These must in fact have holes with a corresponding hole pattern. This is particularly disadvantageous because only a very specific abrasive can be used with a given sanding pad. In addition, when attaching the abrasive to the sanding pad, the relative orientation of the sanding media to the sanding pad must be taken into account so that the holes in the abrasive are congruent with the holes in the sanding pad, thus allowing extraction. Constructively complex solutions to this problem are z. B. off EP 1 977 858 or WO 2009/088772 A2 known.

Disclosure of the invention

It is therefore an object of the present invention to provide a holding body for a flexible abrasive, in particular a sanding pad, with a mounting surface for securing a flexible abrasive, with the various flexible abrasives can be used regardless of their hole pattern and with the suction effect of the relative orientation of an abrasive to the holding body is virtually independent.

This object is achieved by a holding body for a flexible abrasive according to independent claim 1.

In some embodiments, the holding body is designed as a sanding pad. In other embodiments, the holding body may also be designed as a hand sanding block, as a sanding plate or as an adapter. An adapter can be used, for example, to adapt a flexible abrasive to a sanding pad.

The holding body includes a fixing layer having a mounting surface for fixing a flexible abrasive.

The holding body further comprises a support body with a support surface. This support surface supports a retaining surface of the attachment layer. Such a support body can press the attachment layer and thus attached flexible abrasive to a surface to be machined. The support body is air and dust permeable, consists in particular of air and dust permeable material. Alternatively, however, the support body could also have a large number of openings with a small diameter.

The holding surface may be opposite the attachment surface of the attachment layer. In particular, the support surface may be connected to the support surface.

According to the invention, the attachment layer consists of an air- and dust-permeable material. An air and dust extraction is thus both through the attachment layer as well as through the support body through possible.

For the purposes of the present invention, a material is referred to as dust-permeable, if it is permeable by grinding dust, which is usually obtained during the machining of workpieces. Typically, the particles of abrasive dust have sizes that are about 10% of the sizes of the abrasive grains. For example, the sizes of the particles of the grinding dust may be in the range of 1 to 200 μm. Furthermore, a material is referred to as permeable to air, if it is traversed by suction at Absaugunterdrücken, which are common during grinding, of air. In particular, the material may be permeable to air such that an air extraction by means of an exhaust system is possible, which generates a volume flow of about 200 to 500 m ³ / h.

Due to the formation of the attachment layer, a substantially uniform suction of air and sanding dust over the entire mounting surface is possible - and not only in the area of individual holes. For this reason, the holding body can be used with any holes having flexible abrasive: The holes of the flexible abrasive are always located in a region of the mounting surface, through which an air and dust extraction is possible. In addition, the suction effect, in contrast to known holding bodies practically not dependent on the relative rotational position between the grinding disc and flexible abrasive. In addition, the production of the attachment layer is particularly simple, since the source material (that is, for example, a textile material) does not need to be perforated in a further step.

Preferably, the attachment surface is substantially full-surface. The attachment layer is referred to as essentially full-surface if it contains no further holes other than the material-specific openings or pores. For example, the attachment layer may contain or consist of a textile material. Such a textile material has, due to its production between the threads openings through which air can flow. Contains a full-surface in the context of the invention textile layer except these openings but no further holes. Alternatively, it is also conceivable that the attachment surface has additional perforations in addition to the material's own openings.

Preferably, the attachment surface has mechanical attachment means for securing a flexible abrasive. In particular, these attachment means may be loops and / or hooks protruding from the attachment surface. Such fasteners are both inexpensive and effective. Alternatively, the fastening means may also be designed as mushrooms or anchor T-head form.

In further conceivable embodiments, the attachment surface may be self-adhesive and, for example, comprise a pressure-sensitive adhesive. As a result, the attachment surface can be attached by gluing to a flexible abrasive. The attachment layer can be formed, for example, as a textile material, such as a woven or knitted fabric, which is coated with a pressure-sensitive adhesive. The textile material may be, for example, a suede. Alternatively, the attachment layer may be formed as a grid. In further possible embodiments, the attachment layer may also be formed as an open-cell foam, which is coated with a pressure-sensitive adhesive.

In other conceivable embodiments, the attachment surface may have no fastening means. For example, it may have a substantially planar surface on which a flexible abrasive coated with a pressure-sensitive adhesive can be attached.

Advantageously, the attachment layer contains or consists of a textile material. In particular, it may be a textile material having loops and / or hooks and / or mushroom heads. Such fasteners are also both inexpensive and effective, and can be obtained, for example, from Velcro USA Inc., Manchester, NH 03103, USA. A textile material having hooks can be produced, for example, from a textile material comprising loops, in which the loops are cut open and the textile material Material is subsequently impregnated. Such materials are also known per se.

Particularly advantageously, the support surface supports the holding surface substantially over the entire surface and is in particular substantially completely connected to the entire surface. In this way, the attachment layer and thus also the attached flexible abrasive can be pressed over the entire surface of a surface to be machined.

Particularly advantageously, the support body has an open-cell foam or consists thereof. The foam may include or consist of, for example, polyester-polyurethane, polyether-polyurethane, a prepolymer, melamine, or a combination thereof. Alternatively, however, the support body may for example also contain or consist of a spacer fabric or a honeycomb construction. According to the invention, the support plate is enclosed on its periphery by an air-impermeable stabilizer body.

Preferably, the attachment layer is in flow communication with a suction opening of the holding body, which is spaced from the attachment layer. As a result, sanding dust arising during grinding can be actively sucked off by applying a negative pressure to the suction opening. With particular advantage, the suction opening is arranged on the side opposite the fastening layer side of the holding body. This allows a particularly simple suction.

The holding body may include at least one air chamber for air and dust extraction, wherein the air chamber in fluid communication with the attachment layer and the suction port is in communication.

The holding body may further comprise fastening means for fixing the holder body to a drive. For example, the holding body may be formed as a sanding pad, wherein the fastening means for fixing to a rotatable drive a grinding machine, an eccentric drive a grinding machine, a linear drive a grinding machine or a Combination thereof be formed. Such fasteners to sanding plates are known per se.

The invention also relates to a grinding system which comprises at least one holding body for a flexible abrasive, as described above, in particular a sanding pad, and at least one flexible abrasive. The flexible abrasive is attachable to the mounting surface of the holder body. The flexible abrasive may be a grinding wheel, for example.

The flexible abrasive may have holes through which dust is sucked. A dust extraction is of course also possible if the abrasive as well as the attachment layer consists of an air- and dust-permeable material and other than material own openings or pores does not meet any further holes.

The grinding system may also comprise a plurality of mutually different flexible abrasives. In particular, the hole patterns of the abrasive may differ from each other.

Such a grinding system allows the use of several different flexible abrasives with one and the same holding body. Due to the inventive properties of the holding body and in particular its attachment layer suction of air and dust is possible, regardless of the hole pattern of the abrasive and also on the relative position of the abrasive relative to the holding body, in particular from the relative rotational position of the abrasive to a grinding disc.

In the following the invention with reference to an embodiment and the FIG. 1 explained.

In FIG. 1 is a side sectional view of a holding body according to the invention shown, which is designed as a sanding pad 10. The sanding pad 10 has a cover plate 3 made of glass fiber. The cover plate 3 contains a plurality of suction openings 5 penetrating it in the axial direction, of which only two can be seen here. The cover plate 3 is by means of rivets 6 with a Metal plate 7 connected. At this metal plate 7, a screw 8 is fixed, with which the sanding pad 10 is fastened to a rotating drive of a grinding machine, not shown here. The screw 8 thus serves as a fastener.

In other, not shown embodiments, the metal plate 7, the rivets and 6 and the screw 8 are not part of the sanding pad 10, but part of a machine-side receptacle for the sanding pad 10. In this case, the cover plate 3 forms the attachment means of the sanding pad 10, with the sanding pad 10 is fastened to the drive.

At the side facing away from the metal plate 7 of the cover plate 3, the sanding pad 10 has a support body 4. The support body consists of an air- and dust-permeable, open-cell foam. The foam may include or consist of, for example, polyester-polyurethane, polyether-polyurethane, a prepolymer, melamine, or a combination thereof. In particular, filter foams are suitable. The foam should be particularly waterproof, resistant to aging and fatigue. In addition, it should be able to be exposed to typical working temperatures of about 0 ° C to 180 ° C. In the radial direction of the support plate 4 is enclosed by an air and dust impermeable stabilizing body 2, which consists of foam. With the help of the stabilizing body 2, a lateral air inflow can be prevented.

On the side facing away from the cover plate 3 side of the support body 4, the support body 4 has a support surface 14. With this support surface 14, a holding surface 15 of a fixing layer 1 is connected. As a result, the support surface 14 supports the support surface 15 substantially over the entire surface. The connection between support surface 14 and holding surface 15 can be achieved for example by gluing, Flammkaschieren or ultra-high frequency welding. In order to bond the support surface 14 and the holding surface 15 to one another, they are preferably provided only on the surface with an adhesive, for example by kiss coating. In this way it is ensured that the pores in the support body 4 and in the attachment layer 1 are not clogged and also after bonding the desired air and dust permeability preserved. The method of bonding per se is known to the person skilled in the art; The required application rates of the adhesive can be determined by routine experimentation.

The attachment layer 1 is a textile material. Due to the openings between the individual threads of the textile material, the attachment layer 1 is permeable to air and dust. The textile material should be particularly waterproof, resistant to aging and fatigue. In addition, it should be able to be exposed to typical working temperatures of about 0 ° C to 180 ° C. Such textile materials per se are known to the person skilled in the art. Furthermore, the attachment layer 1 is circular and full-surface. Apart from the openings between the threads of the textile material, the attachment layer 1 therefore has no further holes. This ensures a full-surface suction of air and sanding dust.

The textile material of the attachment layer 1 has on the holding surface 15 opposite mounting surface 11 a plurality of hooks, which, however, are not recognizable in the drawing. The hooks form mechanical fasteners for securing a flexible abrasive. For this purpose, the flexible abrasive loops, which can engage in the hooks of the mounting surface 11. In FIG. 1 the flexible abrasive is designed as a grinding wheel 9. In the drawing, the grinding wheel 9 is shown separated from the sanding pad 10 in the sense of an exploded view.

During operation of the sanding plate 10 with the grinding wheel 9 attached thereto, air and dust can be sucked through the holes 12 in the grinding wheel 9, through the fixing layer 1, through the supporting body 4 and through the outlet openings 5. The air and dust flow is denoted by S. The suction effect is thus practically independent of the hole pattern of the grinding wheel 9 and also of the relative rotational position between the grinding wheel 9 and the sanding pad 10.

Claims (9)

1. Holding body for a flexible grinding means, in particular a grinding pad (10), comprising a fastening layer (1) with a fastening surface (11) for fastening a flexible grinding means (9) and a supporting body (4) with a supporting surface (14), which supports, in particular is connected to, a holding surface (15) of the fastening layer (1) that is, in particular, opposite from the fastening surface (11), wherein the supporting body (4) consists of an air- and dust-permeable material, wherein the fastening layer (1) consists of an air- and dust-permeable material, characterized in that the supporting body (4) is enclosed at its periphery by an air-impermeable stabilizing body (2) .
2. Holding body according to Claim 1, characterized in that the fastening surface (11) is substantially full-surfaced.
3. Holding body according to either of Claims 1 and 2, characterized in that the fastening surface (11) has mechanical fastening means for fastening a flexible grinding means (9), in particular loops and/or hooks protruding from the fastening surface (11) .
4. Holding body according to one of the preceding claims, characterized in that the fastening layer (1) comprises or consists of a textile material, in particular a textile material having loops and/or hooks and/or stud heads.
5. Holding body according to one of the preceding claims, characterized in that the supporting surface (14) supports, in particular is connected to, the holding surface (15) substantially over the full surface.
6. Holding body according to one of the preceding claims, characterized in that the supporting body (4) comprises or consists of an open-cell foam material, a knitted spacer fabric or a honeycomb structure.
7. Holding body according to one of the preceding claims, characterized in that the fastening layer (1) is in flow connection with a suction removal opening (5) of the grinding pad (10), which is at a distance from the fastening layer (1), in particular is arranged on the side of the grinding pad (10) that is opposite from the fastening layer (1) .
8. Holding body according to one of the preceding claims, characterized in that the holding body has fastening means (8) for fastening the holding body to a drive, in particular to a rotatable drive and/or an eccentric drive and/or a linear drive.
9. Grinding system comprising

   - at least one holding body for a flexible grinding means, in particular a grinding pad (10), according to one of the preceding claims and

   - at least one flexible grinding means (9), which can be fastened to the fastening surface (11) of the holding body.

Images