Improved abrasive device

Abstract

 Improved abrasive device for appliance of a rotating, abrasive surface, having an upper hub wheel 10 and a lower hub wheel, which are arranged within each other, wherein the upper hub wheel 10 and the lower hub wheel are connected by threads and said threads are formed on the steep, matching sides 11of the hubs, resulting in reduced wear and improved handling. Advantageously a socket-sleeve 13 reduces the risk of entanglement, while a cut-out 16 facilitates assembly / disassembly of the hub wheels; a horizontally extending, abrasive media 23 allows improved, optical control during application.

Description

[0001] The present invention is directed at an improved abrasive device according to the preamble of independent claims.

TECHNICAL AREA

[0002] The general technical area is the area of abrasives, which are used to condition and/or clean surfaces. Depending on rougnhess and grain-size of an abrasive media and the condition and time of application of said media such abrasives allow a multitude of actions, ranging from rough, substantial removal of matter over cleaning and polishing applications to honing and/or smoothening especially planar surfaces for special applications.

[0003] CH 257 128 A1 demonstrates common and established designs and known measures within this area. Disc-shaped or ring-shaped solid bodies are known, which are fixed or attached to a rotating drive as shown within said document in figure 4. The rotating disc or ring carries the abrasive media, which will affect a material, when said material is brought into contact with the rotating surface of the disc or ring. Applications like polishing, grinding or cutting are thus possible. Likewise US 2004 / 0053569 A1 teaches that usual hub-cleaning is carried out by applying a grinding-wheel or sand-paper. To obtain a smooth and clean surface this document proposes to apply a ring-shaped grinding body removably to the annular face of a rotatable, bell-shaped seat body, which in turn can be operated manually. However said bell-shaped seat-body will only allow attachment of abrasive media at its annular end face. Furthermore the seat body consists out of a single, bell-shaped, hard polymer-body, thus disadvantageously transducing any impact or jolt directly into the hard polymer structure, which will cause direct stress and related wear of the body within the force-transducing sections.

[0004] From US 4,694,615 A1 a depressed-center grinding wheel is known, wherein said grinding hub wheel is attached to a rotating rod via a retaining nut and a matchingly cup-shaped backing-flange.

[0005] A general problem of said rotating, abrasive media is the detrimental impact of the uneven structures which have to be conditioned: Uneven elevations within a surface produce jolts and impacts, which affect directly the force-fitting and force-transducing connection of abrasive media/ carrier and rotating drive. The established connection like a central, threaded rod and a clamping nut are thus subject of repeated jolts and impacts and suffer considerable wear.

[0006] From prior art several designs are known, which try to improve this common flow of forces:

PRIOR ART

[0007] From GB 718,149 A a locking-mechanism is known, which links a grinding-head to a rotating column. Said locking-mechanism uses a tapered head, which locks into a cylindrical blind hole by spring-actuated tension. If an impact exceeds a preset limit said tapered bolt is pushed outward into a slipping position, thus avoiding destructive forces due to a crammed abrasive media which is blocked in movement.

[0008] From DE 34 39 230 C1 it is known to link an abrasive, rotating media to a drive via an elastomer-body, dampening jolts and impacts within the solid, elastomeric structure.

[0009] From DD 258 765 A1 a device is known, wherein two hub-wheels are arranged within each other so as to fasten a ring-shaped abrasive media, which is arranged between their outer, extending rims. Such a clamping fixation allows sliding as well as moving of the abrasive media in case it becomes blocked on a rough surface, but will also induce jolts via the central joint and shaft into the drive. The present invention started from this type of generic design.

[0010] A disadvantage of presently available devices is, that they do not allow attachment of all abrasive media available. While some require at least a ring-shaped, planar surface for reversible attachment of pads or sponges, others require form-fittingly cut-outs or clamping rims. No device is known which would allow quick and easy exchange of one type of abrasive media with another, e. g. exchanging a C-shaped ring-body with a flat, circular pad.

[0011] A further problem is that many devices still transduce impacts or jolts directly into the centrally attached drive and its connection with the media-holder / holder. Using dampening structures, which have elastic properties, results in a connection of increased, elastic force, making disassembly difficult and often requiring specials tools or wrenches so as to loosen the connection.

[0012] A further problem is that alloys, which have the required stability and strength to withstand jolts or impacts, are expensive and will wedge tight once dust enters a threaded connection; however, dust is omnipresent in the case of abrasive media applications, resulting in threaded connections, which often lock irreversibly, making disassembly almost impossible.

[0013] A further problem is that many abrasive devices have special extensions and/or special adaptor connectors so as to allow attachment to a drive; in case such an adaptor is lost or damaged, the whole device becomes useless.

[0014] Object of the present invention is to provide an abrasive device which overcomes disadvantages known from prior art and provides an improved device for appliance of a rotating, abrasive surface.

[0015] Solution to said object is according to the features of independent claims. Advantageous and/or preferable features which address further problems are to be found in dependent claims and the following specification.

SUMMARY OF INVENTION

[0016] According to the invention an improved abrasive device for appliance of a rotating, abrasive surface, having an upper hub wheel (10) and a lower hub wheel (20), which are arranged within each other, is characterised in that the upper hub wheel (10) and the lower hub wheel (20) are connectable by threads (30), wherein said threads (30) are formed on the steep, matching sides (11), (21) of the hubs.

DESCRIPTION OF INVENTION AND ADVANTAGEOUS FEATURES

[0017] A 'hub wheel' is a generally bell-shaped or cup-shaped part, having an outer, horizontally extending rim and a 'hub', i. e. an upwardly impressed, inner core. Said hub/core section has a symmetrically extending, tube-shaped section, connecting the lower, outer rim with an upper apex. In case of an essentially vertical tube and a horizontal apex such a hub wheel has a cross-cut resembling a pot with vertical sides in upside-down position with a broad, extended rim, while a tapered tube-shape will result in a cross-cut of trapezoidal appearance, having inclined sides connecting the lower, broader rim with the upper, smaller apex. Throughout the present specification 'horizontal' shall designate a direction at essentially right angle to the axis of rotation, while 'vertical' shall designate a direction essentially in parallel to the axis of rotation. Furthermore, the horizontally extending rim of a hub wheel shall be designated as the 'lower' part of a hub wheel, while the impressed core and its terminating apex will be designated as 'upper' part, which are thus 'above the rim'.

[0018] The two hub wheels (10, 20) of the present invention are to be arranged within each other, i. e. the lower hub of lower hub wheel (20) is equal or smaller in diameter and/or - in case of a trapezoidal shape - has an outer contour which is equal or less in size compared to the dimensions of the cavity/hub of the upper hub wheel (10). Thus the lower hub wheel (20) can be arranged within the upper hub wheel (10), the lower hub extending into the upper hub respectively.

[0019] The lower hub wheel (20) has at least one outer thread, while the upper hub wheel has at least one inner thread, both said threads (30) arranged in areas, where the two hub wheels (10,20) are arrangeable close enough to each other to allow interaction of said threads (30), which are positioned on steep, matching sides (11, 21) of the two hubs. It goes without saying that in 'matching' areas threads (30) are deep enough to interact effectively and surfaces are close enough in geometry to allow sufficient engagement. Preferably the threads (30) are constructed to interact with a size of gap between threads which allows thermal expansion of the lower hub wheel (20) for cutting or abrading/polishing a material which generates substantial frictional heat like a metal oxide / ceramic. Preferably the threads (30) have an elastic, exchangeable component in their terminating section, allowing setting elasticity of tight connection to required values; more preferably said elastic component is an elastic polymer; most preferably said elastic component is arranged in the enclosed apex section between the hub wheels (10, 20).

[0020] Assembly of the inventive device is carried out by screwing the lower hub wheel (20) into the upper hub wheel (10) until a tight connection is provided; preferably a sense of rotation is a preset value indicated on the outside of the upper hub wheel (10) and opposite to the sense of connection, i. e. during use the lower hub wheel (20) is constantly pushed into the upper hub wheel (30) by the frictional drag, improving connection, performance and reliability.

[0021] By arranging the threads (30) closer to the outer rim, jolting forces exerted onto the outer rim have a much smaller leverage while the thread as such becomes substantially longer. The inventors deem these two effects to be responsible for the improved performance of the inventive device: The threads (30) are much more durable and show a significant decrease in wear, while the connection of hub wheels (10, 20) shows no tendency to wedge tight in an overtight, locked connection. The threads (30) are only deformed elastically, even when conditioning inhomogeneous material like concrete admixtures with roughly crushed, ceramic additives, wherein sudden changes in frictional drag are inevitable.

[0022] Advantageously the claimed device is characterised in that the relation outer diameter (22) of lower hub wheel (20) to inner diameter (25) of lower hub wheel (20) is not larger than 8/1. Keeping the diameters in this range allowed use of softer metals and alloys, reducing cost of production considerably.
Preferably the relation outer diameter (22) of lower hub wheel (20) to inner diameter (25) is kept between 5/1 and 1,6/1. Within this range polymer-materials can be used to provide at least one of the hub wheels, while keeping performance and wear-resistance at top level. Especially composite bodies having a metal endo-skeleton and a plastic body with preferably fiber-reinforced polymeric component, could be used throughout all applications without the metal endo-skeleton separating from the surrounding polymer matrix.
Most preferably the relation outer diameter (22) of lower hub wheel (20) to inner diameter (25) is kept between 3,1/1 and 1,7/1, allowing durable combinations of materials of increased elastic nature while having less strength. Such combinations are especially versatile in receiving differing abrasive media ranging from abrasive rings having a c-shaped cross-cut, which are to be arranged on the lower hub wheel (20) and being clamped elastically along the extending rims of both hub wheels (10, 20), over elastic strips or pads which are attached to the lower hub wheel (20) by adhesive binding, to solid composite bodies containing an abrasive in a matrix, which are attached reversibly by a hook-and-loop area or likewise threaded connection, allowing various types of operations like cutting and massive abrading, without requiring further special tools or devices.
In a most advantageous embodiment the abrasive media consists of several parts, which are detachably connected, to allow a series of operations without even one change; i. e. an elastic, c-shaped ring carrying an elastic pad with an attached rough, abrasive strip allows rough grinding, removal of strip, fine grinding using the pad, removal of pad and concluding polishing using a fine polishing agent arranged within the polymeric matrix of said ring, requiring only removal of respective abrasive media-part after completion of each step. In view of the predescribed the present invention also discloses an advantageous method for abrading and subsequent polishing comprising the use of at least three removably connected, abrasive media.

[0023] Advantageously the claimed device is characterised in that the upper hub wheel (10) has a socket sleeve (13), said socket sleeve (13) form-fittingly encasing a central attachment means for transduction of rotational force. Transduction of rotational force, i. e. imparting rotation, requires considerable forces. By encasing a respective central attachment means with a socket sleeve dangerous gaps or edges are covered and sealed, reducing for example the risk of dangerously engaging operator's clothing. Preferably said socket sleeve (13) has covering sections formed from an elastic low-friction polymer, which snugly cover and encase gaps and ridges and the surface of which is so low in friction, that even in case of entanglement an effective wind-up is most unlikely; additionally such a low-friction material has the advantageously decreased tendency to accumulate dust and will prevent dust from entering into the force-fitting connection between a drive and the abrasive device.

[0024] Advantageously the claimed device is characterised in that the upper hub wheel (10) has a lock-in mechanism (14) for transduction of rotational force. A lock-in mechanism (14) has engaging or gripping means like steel-balls, which can be brought into engagement with a drive or respective gear, preferably by manual operation. Thus a lock-in mechanism (14) advantageously allows quick and easy exchange of device and/or drive manually, requiring no further tool. Examples of established designs in this area are given for example in GB 1108 248 A1 or US 3 816 015 A1, which are incorporated by reference concerning the respective measures and constructional features.
Preferably the lock-in mechanism (14) is designed in combination with a socket-sleeve (13), providing a quick-change mechanism, which advantageously improves security during use and preferably prevents dust from entering the lock-in mechanism (14), thus reducing wear considerably.
Preferably the lock-in mechanism (14) comprises an outer, symmetrical hinge clamp, which allows quick release-action by disengaging a clamp with one movement, wherein said clamp has an even, radial distribution of weight, nullifying any risk of opening due to centrifugal forces during use.
Preferably the lock-in mechanism (14) comprises a drive-lock mechanism, which allows locking the device in a relative position so as to facilitate unscrewing the lower hub wheel (20).

[0025] Advantageously the claimed device is characterised in that the upper hub wheel (10) has a central bush (15) as a central attachment means, said central bush (15) being attachable to a polygonal shank allowing transduction of rotational force. A polygonal shank has edges, which can effectively interact and engage with a respective retainer; such systems are known from special screwdrivers and matchingly recessed screws like hexagon screws.
Preferably the central bush (15) has engagement means which allow engaging several, common types of shanks.
Preferably the central bush (15) has engagement means comprising a lock-in mechanism (14) comprising preferably metal disks and/or metal balls of a high-strength alloy so as to be able to receive and grip tightly a polygonal shank upon insertion.
Preferably such a central bush is attached to the upper hub-wheel reversibly, most preferably via an elastic, durable polymer, which may be removed mechanically in combination with embrittling, excessive heat, but will provide a durable, elastic, force-transducing connection otherwise.

[0026] Advantageously the claimed device is characterised in that the upper hub wheel (10) has a central attachment means which allows attaching of pneumatic drives and/or wrenches. Pneumatic drives / wrenches provide two major advantages; firstly pneumatic systems are often already present and available even in small-scale workshops, secondly a pneumatic drive is powered by pneumatic pressure, i.e. force is exerted elastically and smoothly due to the pneumatic expansion of the driving, pressurised air. Thus even small workshops will be able to use such a preferable, abrasive device with improved, smooth acceleration, improved speed and even acceleration-characteristics, resulting in an improved overall performance at an extremely low price, as a special drive does not have to be bought. In view of this the present invention also discloses an advantageous use of the claimed abrasive device.
Preferably such a matching central attachment means comprises a security valve, which will release pressure upon reaching excessive rotational speed, thus improving security of application with a very simple and effective, constructional feature.

[0027] Advantageously the socket-sleeve (13) is form-fittingly encasing the central bush (15); the central bush (15) is a central attachment means which is attachable to a polygonal shank, allowing transduction of rotational force. The lock-in mechanism (14) is arranged within the central bush (15) and is able to lock into optional grooves of a shank, improving the locked connection in stability and safety. The socket sleeve (13) is connected to the lock-in mechanism (14) via a spring-loaded connection, providing quick change of an attached shank as well as keeping the socket sleeve (13) in encasing position via spring-tension while polygonal shank is attached. The central bush (15) allowing attaching of pneumatic drives and/or wrenches, results in a combination of features which improve compliance, usability and safety in an excelling manner.

[0028] Advantageously the claimed device is characterised in that the lower hub wheel (20) comprises at least one abrasive media (23) selected from the group consisting of pad, strip, disk, sponge, composite body, sponge containing abrasive particles, fiber body, fiber body containing abrasive particles, filaments, fabric, woven fabric, non-woven, fiber body containing metal fibers, detachable pad, detachable strip, detachable disk, detachable sponge containing abrasive particles, detachable fiber body, detachable fiber body containing abrasive particles, detachable filaments, detachable fabric, detachable woven fabric, detachable non-woven, detachable fiber body containing metal fibers, glued-on pad, glued-on strip, glued-on disk, glued-on sponge, glued-on fiber body, glued-on filaments, glued-on fabric, glued-on woven fabric, glued-on non-woven.
Preferably an abrasive media (23) is attached using a glue; glues are well-established and provide a series of advantageous properties (e. g. removable or permanent glues, elastic, duroplastic or thermoplastic glues or combinations thereof) which can be adapted to requirements. Most preferably a glue is set to provide a permanent connection of the abrasive media but will decompose / detach in case of overheating and/or application of a solvent, thus improving potentially both security (thermal decomposition upon excessive heat) as well as usability (removable/exchangeable by use of a solvent).
Preferably the abrasive media (23) is/comprises a fabric. Fabrics are woven with threads; nature and arrangement of said threads provides selectable, advantageous features, e. g. a plain weave of different fibres having a preset amount of carbon fibres and polymer fibers with abrasive particles will provide a sheet-like abrasive media having two sides of equal effectivity, wherein the carbon fibers ensure a reducing, chemical condition while the abrasive particles produce a freshly uncovered surface, providing optimum conditions for subsequent ly coating a surface with an oxidising coat or lacquer.
Preferably the abrasive media (23) is/comprises a non-woven like a fleece, which is especially advantageous for polishing applications, especially in the case of randomly and evenly distributed, fine natural fibers, having a natural coating of oils/fats.
Preferably the abrasive media (23) comprises an abrasive structure of improved rigidity like a strip or composite bristles, which allow transduction of higher forces while also providing abrasive particles within a matrix for improved, abrasive action. Such structures allow a quick and considerable removal of material in advantageous combination with improved stability of the abrasive media (23).
Preferably the abrasive media (23) has a diameter, which is not larger than 130% of the diameter of the lower hub wheel (20), keeping the leverage of jolts and impacts in a preset range of strength so as to ensure excelling wear-resistance of the connection of the two hub wheels (10,20) even when carrying out cutting or spot-abrading operations.

[0029] Advantageously the claimed device is characterised in that at least one hub wheel (10, 20) consists at least partially of at least one material selected from the group consisting of polymer, copolymer, terpolymer, copolymerised prepolymer, PP, ABS, metal, light metal, aluminum, abrasive material, preferably consists at least partially of a composite material, preferably a composite material containing a metal endo-skeleton, most preferably a composite material containing a metal endo-skeleton and a component containing an abrasive media.
Preferably PP (polypropylene) is applied in parts which have to provide strength and heatresistance; in use a PP-carrier could withstand short peak-temperatures of up to 130°C during cutting operations without showing any decrease in stability.
Preferably ABS is applied in parts which have to provide stability in aqueous, aggressive conditions like polishing or cutting while using an aggressive, aqueous acid, base or oxidising cutting oil.
Preferably aluminum is applied in parts which require a large, abrasive surface in combination with improved strength; aluminum provides sufficient stability while keeping weight exceptionally low, allowing especially manual operations at improved user-compliance: The user will find such a tool light-weight and easy to handle, while providing excelling abrasive performance.

[0030] Advantageously the claimed device is characterised in that the upper hub wheel (10) has at least one cut-out (16) in its side (11) and the lower hub wheel (20) has at least one hole (24) in its side (21), wherein said hole (24) is reachable through the cut-out (16) when upper hub wheel (10) and lower hub wheel (20) are in connected arrangement.

[0031] A hole (24) provides the possibility to insert a rod or tool for exerting a stronger force in order to disassemble the abrasive media: The matching cut-out (16) allows insertion of a rod or tool into the hole (24); the hole may be any kind of hole comprising pin holes, blind holes as well as through holes, as long as force-transducing insertion of the rod or tool is possible so as to provide the respective leverage.
Preferably the mounted abrasive device is fixed in position by locking the upper hub wheel (10) via the respective drive or with a locking-means.
The combination of hole (24) and cut-out (16) allows the predescribed application of a rod or tool in order to quickly disassemble upper hub wheel (10) and lower hub wheel (20), allowing advantageously a quick change and/or adaptation of the abrasive device especially in applications, where the established abrasive devices are cumbersome to handle and/or adapt.

[0032] Further advantages will be apparent in view of the following explanation of advantageous embodiments. It is to be understood that the predescribed, preferable and/or advantageous features and following embodiments are not to be seen as restricting the present invention to the disclosed features or their respective combinations: Additional advantageous/preferable features and further combinations of features as explained within the specification or in differing combination may be incorporated additionally within the subject-matter of independent claims without leaving the scope of the invention / claimed protection.

SHORT DESCRIPTION OF FIGURES

[0033] The figures demonstrate schematically.....

Fig. 1 an advantageous embodiment of an upper hub wheel (10)

Fig. 2 an advantageous embodiment of a lower hub wheel (20)

Fig. 3 an advantageous embodiment of an improved abrasive device in exploded view

Fig. 4 an advantageous embodiment of an assembled improved abrasive device

Fig. 5 an advantageous embodiment of an assembled improved abrasive device having two trapezoidal hubs

DETAILED EXPLANATION OF INVENTION IN VIEW OF

ADVANTAGEOUS EMBODIMENTS

[0034] An advantageous embodiment of an improved abrasive device for appliance of a rotating, abrasive surface has an upper hub wheel (10) and a lower hub wheel (20), which are arranged within each other, wherein

• the upper hub wheel (10) and the lower hub wheel (20) are connectable by threads (30),
• said threads (30) are formed on the steep, matching sides (11), (21) of the hubs
• the relation outer diameter (22) of lower hub wheel (20) to inner diameter (25) of lower hub wheel (20) is between 3,1/1 and 1,7/1
• the upper hub wheel (10) has a socket sleeve (13), said socket sleeve form-fittingly encasing a central bush (15), said central bush (15) being a central attachment means which is attachable to a polygonal shank allowing transduction of rotational force,
• the upper hub wheel (10) has a lock-in mechanism (14) within its central bush (15), wherein said lock-in mechanism (14) is built to lock into optional grooves of a shank,
• the socket sleeve (13) is connected to the lock-in mechanism (14) via a spring-loaded connection, allowing quick changing of an attached shank as well as keeping the socket sleeve (13) in encasing position while polygonal shank is attached,
• the central bush (15) allowing attaching of pneumatic drives and/or wrenches,
• the lower hub wheel (20) comprising at least one abrasive media (23) selected from the group consisting of strip, fabric, woven fabric, non-woven, filament body,
• the upper hub wheel (10) has at least one cut-out (16) in its side (11),
• the lower hub wheel (20) has at least one hole (24) in its side (21),

and wherein said hole (24) is reachable through the cut-out (16) when upper hub wheel (10) and lower hub wheel (20) are in connected arrangement.

[0035] Fig. 1 shows an advantageous embodiment of an upper hub wheel (10) having a socket sleeve (13), a steep, essentially vertical side (11) of a central hub, said hub having cut-outs (16) within said sides.
The snugly encasing socket sleeve (13) is directly attached to the horizontal apex of the upper hub wheel (10), leaving no gaps or edges which would endanger a user during application.
The cut-out (16) is of preferable, elongated, slotlike shape and will keep several as well as differing holes of a connected lower hub wheel (20) well reachable. The slot-like form of the cut-out (16) allows connection of different, lower hub wheels (20), all of which will be reachable via said advantageously versatile cut-out (16). Thus a combination of this upper hub wheel (10) with a lot of types of a lower hub wheel (20) provides a failproof mode of connection: The elongated shape ensures that - no matter how the respective threads (30) are brought into contact - a respective hole (24) will be well reachable.

[0036] Fig. 2 shows an advantageous embodiment of a lower hub wheel (20), having a steep, essentially vertical side (21) of a central hub, wherein the lower part of the side is equipped with a thread (30), while the upper part has four equally distanced holes (24) arranged on a horizontal plane. While the thread (30) allows secure, improved connection to an upper hub wheel (10), the holes (24) provide the possibility of quick disconnection, using a rod, tool or wrench to connect to said hole (24) via a cut-out (16) and apply a separating force with considerable leverage.

[0037] Fig. 3 shows an advantageous embodiment of an improved abrasive device in exploded view, wherein components are positioned at a distance to each other. The upper hub wheel (10) and the lower hub wheel (20) are to be arranged within each other, connectable by threads (30), the thread (30) of the upper hub wheel only partially being visible through the cut-out (16). The threads (30) are formed on steep, essentially vertical, matching sides (11), (21) of the hubs, the matching, inner, vertical side of the upper hub wheel (10) not being visible. Such a configuration in assembled state would resemble a double-wall, vertically extended pot in upside-down orientation, resting on its horizontally extending rim, if viewed along a vertically intersecting plane of view. The relation of outer diameter (22) of lower hub wheel (20) to inner diameter (25) of lower hub wheel (20) is kept between 3,1/1 and 1,7/1, thus allowing advantageous structures and materials to be selected for one or both hub wheels (10, 20). The upper hub wheel (10) has a socket sleeve (13), which encases a central bush (15) snugly, improving advantageously security during application. The central bush (15) serves as a central attachment means, attachable to a polygonal shank and allowing transduction of rotational force. A lock-in mechanism (14) within the central bush (15) allows to lock into optional grooves of a shank with metal disks of a high strength alloy, improving firmness of connection as well as stability of force transduction. The socket sleeve (13) is connected to the lock-in mechanism (14) via a spring-loaded connection, providing a combined quick-change mechanism to change an attached shank or drive and keeping the socket sleeve (13) in encasing position while the polygonal shank is in attached position. The central bush (15) allows attaching of pneumatic drives and/or wrenches, providing a low-cost device with much smoother and durable applicability. The lower hub wheel (20) comprises at least one abrasive media (23) selected from the group consisting of strip, fabric, woven fabric, non-woven or filament body. A filament body consists advantageously of monofile, strong fibers, which may advantageously serve as bristles with an exceptional amount of pressure exerted along their tips, resulting in an extremely effective, abrasive action in case of monofile fibers carrying abrasive particles within their carbonaceous and/or polymeric matrix. The abrasive media extends horizontally, having an outer rim of larger diameter than the lower hub wheel (20), providing an exposed outer rim, which allows abrading and/or cutting spot-operations on a surface. The upper hub wheel (10) has at least one cut-out (16) in its side (11), matching the at least one hole (24) of the lower hub wheel's (20) side (21). Said hole (24) is reachable through the cut-out (16) when upper hub wheel (10) and lower hub wheel (20) are in connected arrangement, allowing a quick, improved disassembly of upper hub wheel (10) and lower hub wheel (20) in case the abrasive device has to be adapted to further and/or different measures.

[0038] Fig. 4 shows an advantageous embodiment of an assembled improved abrasive device, for example according to Fig.3. This figure demonstrates the smooth and continuous outer shape of the advantageous abrasive device in assembled position due to the socket sleeve (13) and advantageously matching diameters of the outer rims of upper hub wheel (10) and lower hub wheel (20). Advantageously the abrasive media (23) has a horizontally extending, outer rim, which gives better, optical control during application and allows a much easier removal by simply peeling off the media manually, using the outer rim as a flap or handle.

[0039] Fig. 5 shows a schematic cross-cut of an advantageous embodiment of an assembled improved abrasive device having two trapezoidal hubs, wherein the threads (30) are arranged on tilted sides. The inclination of said sides within this special embodiment results in a smaller area, wherein the threads (30) can effectively interact. On the other hand a trapezoidal outer shape of the hub reduces advantageously the risk of dangerous entanglement. As can be seen in this figure, threads (30) may also comprise a multitude of short, interacting threads (30), which will effectively interact in a small area and preferably allow a considerable angle of inward-inclination of sides (11, 21) of up to 45 degrees (90 degrees designating vertical arrangement / no inclination); several, short, parallel threads (30) provide the advantage of a quick-release connection between upper hub wheel (10) and lower hub wheel (20): The number of turns needed to bring the threads into tight connection is much reduced. Connection of hubs is thus achievable by a short twist, most preferably not exceeding 270° (360° designating the full circle twist). Such a connection is very easy to use in combination with the predescribed cut-out (16) and matching hole (24), using a simple rod or screw-driver for leverage, most preferably allowing complete assembly / disassembly in combination with matching, slot-like, sloped cut-outs (16), which will keep the holes (24) reachable along the full, needed twist.

List of reference numbers

[0040] 

10

upper hub wheel

11

side

13

socket sleeve

14

lock-in mechanism

15

central bush

16

cut-out

20

lower hub wheel

21

side

22

outer diameter

23

abrasive media

24

hole

25

inner diameter

30

threads

Claims

1. Improved abrasive device for appliance of a rotating, abrasive surface, having an upper hub wheel (10) and a lower hub wheel (20), which are arranged within each other, characterised in that the upper hub wheel (10) and the lower hub wheel (20) are connectable by threads (30), wherein said threads (30) are formed on the steep, matching sides (11), (21) of the hubs.

2. Device according to the previous claim, characterised in that the relation outer diameter (22) of lower hub wheel (20) to inner diameter (25) of lower hub wheel (20) is not larger than 8/1, preferably kept between 5/1 and 1,6/1 , most preferably kept between 3,1/1 and 1,7/1.

3. Device according to one of the previous claims, characterised in that the upper hub wheel (10) has a socket sleeve (13), said socket sleeve (13) form-fittingly encasing a central attachment means for transduction of rotational force.

4. Device according to one of the previous claims, characterised in that the upper hub wheel (10) has a lock-in mechanism (14) for transduction of rotational force.

5. Device according to one of the previous claims, characterised in that the upper hub wheel (10) has a central bush (15) as a central attachment means, said central bush (15) being attachable to a polygonal shank allowing transduction of rotational force.

6. Device according to one of the previous claims, characterised in that the upper hub wheel (10) has a central attachment means which allows attaching of pneumatic drives and/or wrenches.

7. Device according to one of the previous claims, characterised in that the lower hub wheel (20) comprises at least one abrasive media (23) selected from the group consisting of pad, strip, disk, sponge, composite body, sponge containing abrasive particles, fiber body, fiber body containing abrasive particles, filaments, fabric, woven fabric, non-woven, fiber body containing metal fibers, detachable pad, detachable strip, detachable disk, detachable sponge containing abrasive particles, detachable fiber body, detachable fiber body containing abrasive particles, detachable filaments, detachable fabric, detachable woven fabric, detachable non-woven, detachable fiber body containing metal fibers, glued-on pad, glued-on strip, glued-on disk, glued-on sponge, glued-on fiber body, glued-on filaments, glued-on fabric, glued-on woven fabric, glued-on non-woven.

8. Device according to one of the previous claims, characterised in that at least one hub wheel (10, 20) consists at least partially of at least one material selected from the group consisting of polymer, copolymer, terpolymer, copolymerised prepolymer, PP, ABS, metal, light metal, aluminum, abrasive material, preferably consists at least partially of a composite material, preferably a composite material containing a metal endo-skeleton, most preferably a composite material containing a metal endo-skeleton and a component containing an abrasive media.

9. Device according to one of the previous claims, characterised in that the upper hub wheel (10) has at least one cut-out (16) in its side (11) and the lower hub wheel (20) has at least one hole (24) in its side (21), wherein said hole (24) is reachable through the cut-out (16) when upper hub wheel (10) and lower hub wheel (20) are in connected arrangement.

10. Device according to one of the previous claims, characterised in that

- an improved abrasive device for appliance of a rotating, abrasive surface has an upper hub wheel (10) and a lower hub wheel (20), which are arranged within each other,

- the upper hub wheel (10) and the lower hub wheel (20) are connectable by threads (30),

- said threads (30) are formed on the steep, matching sides (11), (21) of the hubs

- the relation outer diameter (22) of lower hub wheel (20) to inner diameter (25) of lower hub wheel (20) is between 3,1/1 and 1,7/1

- the upper hub wheel (10) has a socket sleeve (13), said socket sleeve form-fittingly encasing a central bush (15), said central bush (15) being a central attachment means which is attachable to a polygonal shank allowing transduction of rotational force,

- the upper hub wheel (10) has a lock-in mechanism (14) within its central bush (15), wherein said lock-in mechanism (14) is built to lock into optional grooves of a shank,

- the socket sleeve (13) is connected to the lock-in mechanism (14) via a spring-loaded connection, allowing quick changing of an attached shank as well as keeping the socket sleeve (13) in encasing position while polygonal shank is attached,

- the central bush (15) allowing attaching of pneumatic drives and/or wrenches,

- the lower hub wheel (20) comprising at least one abrasive media (23) selected from the group consisting of strip, fabric, woven fabric, non-woven, filament body,

- the upper hub wheel (10) has at least one cut-out (16) in its side (11),

- the lower hub wheel (20) has at least one hole (24) in its side (21),
and in that said hole (24) is reachable through the cut-out (16) when upper hub wheel (10) and lower hub wheel (20) are in connected arrangement.

Drawing