An abrasion system, a holding device, and a method for forming an abrasion system
The holding device with centring pins and undercut grooves addresses the issues of vibrations and disconnection in abrasive systems by ensuring correct centering and torque transfer, enhancing the stability and ease of use of heavy abrasive tools.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- FLEX TRIM
- Filing Date
- 2026-01-09
- Publication Date
- 2026-07-30
AI Technical Summary
Existing abrasion systems using hook and loop fasteners for connecting abrasive tools to rotating drives face issues such as increased torque leading to disconnection, vibrations, and damage due to improper centering, especially with heavy and high-torque abrasive devices.
A holding device with centring pins that engage disc holes in the connection disc to ensure correct centering and torque transfer, using a hook and loop fastener system, and undercut grooves to secure abrasive strips, allowing easy replacement.
This solution prevents vibrations and disconnection, enabling secure attachment of heavy, high-torque abrasive devices to standard rotating drives while facilitating easy replacement and improved dust extraction.
Smart Images
Figure DK2026050002_30072026_PF_FP_ABST
Abstract
Description
[0001] AN ABRASION SYSTEM, A HOLDING DEVICE, AND A METHOD FOR FORMING AN ABRASION SYSTEM
[0002] Background of the invention
[0003] The invention relates to an abrasion system comprising a rotational drive including a connection disc having a drive front surface to which a holding device is connected. The a holding device includes a holding body comprising a number of undercut grooves formed in an outer surface of the holding body and abrasive strips comprising an abrasive sheet supported on one side by one or more flexible elements, wherein the abrasive sheet and the one or more flexible elements are at one end connected to a holding rail, wherein the holding rail is arranged at least partly in one or more of the number of undercut grooves so that the abrasive sheet and the one or more flexible elements are protruding away from the outer surface of the holding body. The invention also relates a holding device and a method for forming an abrasion system.
[0004] Description of the Related Art
[0005] Abrasion systems usually comprise some sort of motion generating device to which an abrasive tool is connected - such as an abrasive disc, drum, cone, sheet or cub. Abrasion systems are known in many shapes and sizes and used for many different purposes such as grinding, polishing, lapping, sanding and other. The most common motion generating devices are:
[0006] • vibrating sanders or grinders where the abrasive tool is vibrated sideways in one or more directions,
[0007] • orbital or excentric sanders or grinders where the abrasive tool is being rotated around a moving rotational axis so that the abrasive tool is being moved in small ellipses, and
[0008] • rotating sanders or grinders where the abrasive tool is continuously rotated in a single rotational direction around a single fixed rotational axis.However, in many countries Working Environment Acts prohibit the use of vibrating sanders, orbital sanders and eccentric sanders or at least specifies use of these in only limited time periods because the vibrations of the drive system can cause damage to the user in the form of joint pains, Raynaud's syndrome and other. Thus, at least for industrial use rotating grinders and sanders are preferred.
[0009] It is known to connect sanding discs to the rotating sander by means of hook and loop fastener arranged on both the sanding disc and the rotational sander because this makes it fast and easy to replace the sanding disc and this connection system is therefore widespread both for domestic and industrial grinders and sanders - an example of such a hook and loop fastener arrangement can be found in the German utility model DE 20 2023 107 058 Ul. From the European patent application EP 3385032 Al it is also known to attach a sanding disc to a frontside of a support unit of a rotary drive unit by means of a hook and loop fastener arrangement and have pins extend from the frontside into circularly oblong holes in the sanding disc to enable that the sanding disc may be attached in slightly displaced circular positions to enable a more even wear of the sanding disc. However, such pins may strike and thereby damage the object to be sanded - especially if the sanding tool is pressed too hard against the object - and this design cannot be used with of-the-shelf rotary drive units. Furthermore, abrasive tools such as drums and discs, where abrasive strips -comprising an abrasive sheet supported on one side by flexible elements - are slid into undercut grooves in a holding body so that the abrasive sheet and the flexible elements are protruding away from the holding body, are far superior over simple sanding discs in relation to grinding efficiency - examples of such drums and discs with abrasive strips can be found in International patent applications WO 2023202755 Al and WO 2024175161 Al. But the higher efficiency of such drums and discs with abrasive strips also means, that the torque is increased and if such drums or discs are connected to a rotating grinder by means of a hook and loop fastener arrangement, the increased torque may tear the drum or disc of. Furthermore, because such drums and discs with abrasive strips are much heavierthan a sanding disc / sheet it is important that the drum or disc is centered correctly because an off-center placement of the drum or disc will cause unwanted vibrations entailing the same problems as vibrating sanders, orbital sanders and eccentric sanders. Furthermore, such vibrations will increase the risk of the drum or disc disconnecting from the rotational drive.
[0010] An object of the invention is therefore to provide for a more advantageous technique for forming an abrasive system and a holding device for an abrasion system.
[0011] The invention
[0012] The invention provides for an abrasion system comprising a rotational drive including a connection disc having a drive front surface, wherein at least a part of the drive front surface is provided with a drive hook and loop fastener part and wherein the drive front surface is provided with a number of disc holes extending from the drive front surface and into the connection disc. The rotational drive also includes drive means for rotating the connection disc continuously in one rotational direction. The abrasion system further comprises a holding device, wherein the holding device includes a holding body comprising a number of undercut grooves formed in an outer surface of the holding body and abrasive strips comprising an abrasive sheet supported on one side by one or more flexible elements, wherein the abrasive sheet and the one or more flexible elements are at one end connected to a holding rail, wherein the holding rail is arranged at least partly in one or more of the number of undercut grooves so that the abrasive sheet and the one or more flexible elements are protruding away from the outer surface of the holding body. The holding device also includes a device hook and loop fastener part arranged on a device back surface of the holding body, wherein the device hook and loop fastener part is connected to the drive hook and loop fastener part, and a number of centring pins protruding from the device back surface, wherein each of the number of centring pins is engaging a disc hole of the number of disc holes in the drive front surface.Almost all rotational drives are provided with a connection disc having holes in the front surface for dust extraction through matching holes in the abrasive discs / sheets attached to the connection disc. Providing the holding device with centring pins protruding from the device back surface is advantageous in that these centring pins thereby can extend into the disc holes in the connection disc and engage these holes to serve at least two purposes. The first purpose is that the centring pins through their engagement with the disc holes in the connection disc will ensure that the holding device can only be connected to the connection disc when the holding device is correctly centred on the connection disc - hereby avoiding any vibrations that could cause damage to the user and / or the abrasion system. The second purpose is that the centring pins through their engagement with the disc holes in the connection disc can aid in transferring torque through the connection between the holding device and the connection disc and thereby reduce the risk of the hook and loop fastener arrangement giving in and the holding device being tom off the connection disc. Hereby is it possible to connect a relatively large, heavy, and high torque abrasive device as the described holding device - with holding body and abrasive strips - to a standard rotational drive e.g. in the form of a standard rotating sander by means of hook and loop fastener part already present on the rotational drive and thereby enable fast and easy replacement of the holding device.
[0013] In this context the term “rotational drive" is to be understood as any kind of rotational driver capable of rotating the connection disc continuously in one rotational direction around a single fixed rotation axis. I.e., the term includes any kind of rotating sander or grinder, power drill, angle grinder, electrical screwdriver, a dedicated motor device or any other device comprising a motor or a similar device capable of holding or being connected to the connection disc and rotating it.
[0014] Furthermore, in this context the term “drive means” is to be understood as any kind of drive or motor capable of driving the rotation of the connection disc continuously in one rotational direction around a single fixed rotation axis. I.e., the term includesany kind of motor - such as any kind of electrical motor, pneumatic motor, internal combustion engine or other - and any other kind of rotating motion generating device capable of generating the rotating motion of a connection disc.
[0015] Even further, in this context the term “flexible element' is to be understood as any kind of flexible device or attachment capable of providing flexible support to one side of an abrasive sheet. I.e., the term includes any kind of bristles, rubber pad or pads, plastic sheets, brushes or other or any combination thereof.
[0016] In an aspect of the invention, the undercut grooves comprise a first end wall at a first longitudinal end of the undercut grooves and wherein the holding device further comprises a locking part releasably connected to the holding device, wherein the locking part forms a second end wall at a second longitudinal end of the undercut grooves.
[0017] It is important that the abrasive strips are not flung out of the undercut grooves during use of the abrasion system, and it is therefor advantageous to provide end wall in both ends of the undercut grooves to lock the abrasive strips in place. And forming one of these end walls as a locking part that is releasably connected to the holding device is advantageous in that this wall can hereby be removed so that the abrasive strips may easily be replaced when they are worn or if a different type of abrasive strips is needed.
[0018] In an aspect of the invention, the number of centring pins are arranged at the same distance from a rotational axis of the holding device.
[0019] Arranging the centring pins at the same distance from a rotational axis of the holding device - and thereby at the same distance from the rotational axis of the connection disc - so that the centring pins forms a coaxial circle with the holding device and the connection disc is advantageous in that this will ensure an even weight distributionthereby reducing the risk of vibrations. Furthermore, almost all existing rotational drives are provided a circular array of disc holes in the connection disc and by arranging the centring pins at the same distance from a rotational axis of the holding device it is hereby possible to use the holding device with most existing rotational drives.
[0020] In an aspect of the invention, the number of centring pins each taper off towards a protruding free end of the centring pins.
[0021] Making the centring pins taper off towards their protruding free end is advantageous in that this will aid in guiding the pins correctly into the disc holes and thereby enable easier correct centred connection of the holding device to the connection disc.
[0022] In an aspect of the invention, the holding body is made of a plastic material.
[0023] Plastic is inexpensive, light and easy to mould and it is therefore advantageous to form the holding body of a plastic material. This also enables that the relatively complex holding body may be formed e.g., by 3D printing.
[0024] In an aspect of the invention, a longitudinal extent of the undercut grooves is extending substantially parallel with a rotational axis of the holding device.
[0025] Making the longitudinal extent of the undercut grooves extend substantially parallel with the rotational axis of the holding device - and thereby substantially parallel with the rotational axis of the connection disc - is advantageous in that the abrasive strips hereby forms an abrasive drum that are more suited for abrasing complex surface profiles.
[0026] In an aspect of the invention, a longitudinal extent of the undercut grooves is extending substantially perpendicular to a rotational axis of the holding device.Making the longitudinal extent of the undercut grooves extend substantially perpendicular to the rotational axis of the holding device - and thereby substantially perpendicular to the rotational axis of the connection disc - is advantageous in that the abrasive strips hereby forms an abrasive disc that are more suited for abrasing more flat and uniform surface profiles.
[0027] In an aspect of the invention, a maximum pin diameter of the number of centring pins is smaller than a maximum disc hole diameter of the number of disc holes, and a pin centre circle intersecting the centre of each of the number of centring pins is bigger than a disc hole centre circle intersecting the centre of each of the number of disc holes so that an outer edge of each of the number of centring pins is engaging an outer edge of each of the number of disc holes.
[0028] Forming the diameter of the centring pins smaller the diameter of the disc holes is advantageous in that at least a part of these holes may still be used for dust extraction. Furthermore, arranging the centring pins on a bigger circle (i.e. a greater distance from the rotational axis) than the corresponding disc holes in the connection disc so that an outer edge of each of the centring pins is substantially engaging and outer edge of each of the disc holes is advantageous in that this will ensure that the centring pins through their engagement with the outer edge of the disc holes will still ensure correct centring of the holding device and correct transfer of torque even through the centring pins are significantly smaller than the corresponding disc holes.
[0029] In an aspect of the invention, the one or more flexible elements includes bristles.
[0030] Forming the flexible elements as bristles is advantageous is that this locally provides a more flexible support of the abrasive sheet in that the bristles may flex individually as opposed to e.g. a coherent rubber sheet.In an aspect of the invention, the rotational drive is a rotational sander arranged to continuously rotate the holding device in a single rotational direction around a single fixed rotational axis.
[0031] Continuously rotating the holding device in a single rotational direction around a single fixed rotational axis is advantageous in that this will minimize or eliminate vibrations that could be harmful to the user and the abrasion system.
[0032] In an aspect of the invention, the at least some of the number of centring pins comprise a pin centre hole extending all the way through these centring pins and the holding body.
[0033] As previously explained almost all of-the-shelf rotational drives are provided with a connection disc having disc holes in the front surface for dust extraction. However, when at least some of these disc holes are at least partly clogged by the inserted centring pins, the dust extraction effect is reduced. Thus, by providing the engaging centring pins with through going pin centre holes extending all the way through the holding body, the dust extraction effect is increased, and dust is now extracted at the protruding free end of the centring pins, which are closer to the dust producing grinding operation, thus further increasing the effect of the dust extraction.
[0034] The invention further provides for a holding device comprising a holding body comprising a number of undercut grooves formed in an outer surface of the holding body, and abrasive strips comprising an abrasive sheet supported on one side by one or more flexible elements, wherein the abrasive sheet and the one or more flexible elements are at one end connected to a holding rail, wherein the holding rail is arranged at least partly in one or more of the number of undercut grooves so that the abrasive sheet and the one or more flexible elements are protruding away from the outer surface of the holding body. The holding device further includes a device hook and loop fastener part arranged on a device back surface of the holding body,wherein the device hook and loop fastener part is arranged for being connected to a drive hook and loop fastener part of a rotational drive, and a number of centring pins protruding from the device back surface, wherein each of the number of centring pins is arranged for engaging a disc hole in a drive front surface of the rotational drive.
[0035] Providing the holding device with centring pins protruding from the device back surface is advantageous in that these centring pins thereby can extend into disc holes in a corresponding connection disc of a rotational drive and engage these disc holes to serve at least two purposes. The first purpose is that the centring pins through their engagement with the disc holes in the connection disc will ensure that the holding device can only be connected to the connection disc when the holding device is correctly centred on the connection disc - hereby avoiding any vibrations that could cause damage to the user and / or the abrasion system. The second purpose is that the centring pins through their engagement with the disc holes in the connection disc can aid in transferring torque through the connection between the holding device and the connection disc and thereby reduce the risk of the hook and loop fastener arrangement giving in and the holding device being tom off the connection disc. Hereby is it possible to connect a relatively large, heavy, and high torque abrasive device as the described holding device - with holding body and abrasive strips - to a standard rotational drive e.g. in the form of a standard rotating sander by means of hook and loop fastener part already present on rotational drives and thereby enable fast and easy replacement of the holding device.
[0036] In an aspect of the invention, the holding device is the holding device forming part of the abrasion system according to any of the previously discussed abrasion systems. Hereby is achieved an advantageous embodiment of the invention.
[0037] The invention also provides for a method for forming an abrasion system. The method comprises the steps of:• providing a rotational drive including a connection disc having a drive front surface, wherein at least a part of the drive front surface is provided with a drive hook and loop fastener part and wherein the drive front surface is provided with a number of disc holes extending from the drive front surface and into the connection disc, and wherein the rotational drive comprises drive means for rotating the connection disc continuously in one rotational direction,
[0038] • providing a holding device according to any of the previously discussed holding devices,
[0039] • aligning the number of centring pins with the number of disc holes, and • connecting the drive hook and loop fastener part to the device hook and loop fastener part so that each of the number of centring pins is engaging a disc hole of the number of disc holes in the drive front surface.
[0040] Aligning the centring pins with the disc holes is advantageous in that it is not possible to make the drive hook and loop fastener part connect to the device hook and loop fastener part if the centring pins does not fully and correctly engage the disc holes. And making each of the centring pins engage a disc hole of the number of disc holes in the connection disc ensures that the centring pins through their engagement with the disc holes in the connection disc will always be correctly centred - hereby avoiding any vibrations that could cause damage to the user and / or the abrasion system. Furthermore, this ensures that the centring pins through their engagement with the disc holes in the connection disc can aid in transferring torque through the connection between the holding device and the connection disc and thereby reduce the risk of the hook and loop fastener arrangement giving in and the holding device being torn off the connection disc. Hereby is it possible to connect a relatively large, heavy, and high torque abrasive device as the described holding device - with holding body and abrasive strips - to a standard rotational drive e.g. in the form of a standard rotating sander by means of a hook and loop fastener part already present onthe rotational drive and thereby enable fast and easy replacement of the holding device.
[0041] In an aspect of the invention, the abrasion system is an abrasion system according to any of the previously discussed abrasion systems. Hereby is achieved an advantageous embodiment of the invention.
[0042] Figures
[0043] The invention will be described in the following with reference to the figures in which
[0044] fig. 1 illustrates a disc shaped holding device, as seen in an isometric view partly from the back,
[0045] fig. 2 illustrates a disc shaped holding device, as seen in an isometric view partly from the front,
[0046] fig. 3 illustrates a disc shaped holding device, as seen from the back,
[0047] fig. 4 illustrates a disc shaped holding device, as seen from the side,
[0048] fig. 5 illustrates a cross section cutout of a holding device at an abrasive strip, as seen from the side,
[0049] fig. 6 illustrates an abrasion system, as seen from the side,
[0050] fig. 7 illustrates a drum shaped holding device, as seen in an isometric view partly from the back,fig. 8 illustrates a drum shaped holding device, as seen in an isometric view partly from the front, and
[0051] fig. 9 illustrates a drum shaped holding device, as seen from the back.
[0052] Detailed description of related art
[0053] Fig. 1 illustrates a disc shaped holding device 8, as seen in an isometric view partly from the back, fig. 2 illustrates a disc shaped holding device 8, as seen in an isometric view partly from the front, fig. 3 illustrates a disc shaped holding device 8, as seen from the back, fig. 4 illustrates a disc shaped holding device 8, as seen from the side and fig. 5 illustrates a cross section cutout of a holding device 8 at an abrasive strip 12, as seen from the side.
[0054] In this embodiment the holding device 8 comprises a holding body 9 formed as a disc provided with abrasive strips 12, a locking part 20 arranged to fix the abrasive strips 12 in the undercut grooves 10 in the holding body 9 and a device hook and loop fastener part 16 arranged on the device back surface 17 of the holding body 9.
[0055] However, in another embodiment the holding device 8 would not include a locking part 20 or at least not a separate individual locking part 20 e.g., if the abrasive strips 12 were fixed in the undercut grooves 10 by means of a friction fit, interlocking geometry, snap lock or other. Or in another embodiment the holding device 8 could comprise more parts e.g., additional abrasive features, additional features for locking or aligning the holding device 8 in relation to the rotational drive 2, if the holding body 9 was formed from more interconnected parts or other.
[0056] In this embodiment the disc shaped holding body 9 is formed with eighteen evenly distributed radial undercut grooves 10 formed in an outer surface 11 of the holding body 9, wherein the outer surface 11 in this embodiment is a front surface of theholding body 9. I.e., in this embodiment the longitudinal extent of the undercut grooves 10 is extending substantially perpendicular to the rotational axis 22 of the holding device 8 - and thereby to the rotational axis of the rotational drive 2 when the holding device 8 is correctly mounted on a connection disc 3 of the rotational drive 2. However, in another embodiment the undercut grooves 10 could be distributed or angled differently - the undercut grooves 10 could e.g., not be parallel with a diameter of the holding body 9 - and / or the holding body 9 could comprise more radial grooves 10 - such as twenty, twenty -five, thirty or even more - or the holding body 9 could comprise fewer grooves 10 - such as fourteen, ten, eight or even fewer.
[0057] In this embodiment the free end of the abrasive strips 12 is protruding away from the front surface (i.e., outer surface 11) in a direction substantially perpendicular with the device back surface 17 but in another embodiment the abrasive strips 12 could be angled in relation to this perpendicular direction. In this embodiment the undercut radial grooves 10 are extending from a periphery of the holding body 9 towards a centre of the holding body 9 at which the grooves 10 stops just before the centre so that a fixed first end wall 19 (first end wall 19 can be seen in fig. 7) is formed at the first longitudinal end of the undercut grooves 10. In this embodiment the undercut grooves 10 are open at the outer periphery of the holding body 9 so that the abrasive strips 12 can easily be slid out of the undercut grooves 10 if they need to be exchanged. Thus, in this embodiment a locking part 20 - in this embodiment in the form of a relatively thick rubber ring - is encircling and pressing against the holding body 9 at the undercut grooves 10 so that the locking part 20 forms a second end wall 21 at the second longitudinal end of the undercut grooves 10. The rubber ring is in this embodiment arranged in grooves in the radially outer edge of the holding body 9 and the rubber ring - and thereby the second end wall 21 - can thereby easily be removed by pulling the rubber ring off to allow the abrasive strips 12 to be slid out of the undercut grooves 10. However, in another embodiment the locking part 20 could be formed in numerous other ways - such as by a skirt encircling the holding body 9to form a second end wall 21 for each of the undercut grooves 10, where this skirt could be connected to the holding body 9 through threading, friction, bayonet connection, snap lock or other. The locking part 20 could also or instead be formed as individual parts forming individually removable second end walls 21 at each of the undercut grooves 4 - e.g. in the form of screws, snap locks, pins or other - or the locking part 20 could be provided in another way ensuring that the locking part 20 is connected to the holding body 9 during use but also ensuring that the locking part 20 can easily be released from the holding body 9 e.g., when the abrasive strips 12 need to be exchanged..
[0058] In this embodiment the entire holding body 9 is made by 3D printing of a plastic material. However, in another embodiment the holding body 9 could also or instead be made of steel, stainless steel, aluminium and / or another metal, a composite material - e.g., fibre reinforced - or any combination thereof and / or the holding body 9 could be made by moulding, machining or another process or any combination thereof. Furthermore, in another embodiment the holding body 9 could be made of different interconnected parts e.g., made from different materials - such as if the majority of the holding body 9 was made from a plastic material and the centring pins 18 was made of metal and they were connected to the body 9 by means of thread, if the holding body 9 comprised a rubber coating or other.
[0059] In this embodiment the abrasive strip 12 comprises an abrasive sheet 13 which on the backside is supported by a flexible element 14 which in this case is bristles made of a plastic material and in this embodiment the abrasive sheet 13 and the flexible element 14 are mounted in and connected to a holding rail 15 comprising bend sheet metal. In this embodiment the abrasive sheet 13 comprises a sheet of cloth with a layer of abrasive material provided on the frontside (opposite the backside) but in another embodiment the abrasive strip 12 could also or instead comprise abrasive paper, plastic sheets provided with an abrasive material on the frontside or other. And / or the bristles could be made from natural hair, metal, or the flexible element 14could comprise one or more rubber sheets, metal sheets, plastic sheets or other or any combination thereof and / or the holding rail 15 could be moulded plastic, an extruded aluminium rail or other or any combination thereof.
[0060] In this embodiment the undercut grooves 10 are formed as tracks that are wider at the bottom of the tracks than at the outer surface 11 of the holding body 9 and in this embodiment the holding rail 15 of the abrasive strips 12 have substantially the same shape as the undercut grooves 10 so that the abrasive strips 12 may be slid into the undercut grooves 9 from the periphery of the holding body 9 and so that the abrasive strips 12 are substantially locked against axial displacement when mounted in the undercut grooves 9. However, in another embodiment the undercut grooves 9 and / or the holding rail 15 of the abrasive strips 12 could have another shape, such as dovetail shape, an undercut circle, the bottom of the tracks could be wider or have another shape or the undercut grooves 9 and / or the holding rail 15 of the abrasive strips 12 could be formed in numerous other ways ensuring that the strips 12 are locked in the undercut grooves 9.
[0061] In this embodiment the abrasive strips 12 are secured in the holding device 8 by the following method. With the locking part 20 removed from the undercut grooves 10 the abrasive strips 12 are first slid into one or more of the undercut grooves 10 from the periphery of the holding device 8 towards the centre of the holding device 8. The locking part 20 is then releasably connected to the holding device 8, so that it blocks at least a part of each of the undercut radial grooves 10.
[0062] Fig. 6 illustrates an abrasion system 1, as seen from the side.
[0063] In this embodiment the abrasion system 1 comprises a drum shaped holding device 8 mounted on the connection disc 3 of a rotational drive 2 which in this case is a standard rotating sander. However, in another embodiment the rotational drive 2 could be any type of drill provided with a connection disc 3, it could be an anglegrinder, a dedicated device, any kind of rotating sander, grinding, polishing machine or other. In this embodiment the rotational drive 2 comprises drive means 7 in the form of an electrical motor arranged to rotate the connection disc 3 continuously in one rotational direction through a gearbox 28. However, in another embodiment the drive means 7 could comprise a pneumatic motor or any other kind of motor and / or the drive means 7 could instead be coupled directly to the connection disc 3 (i.e. no gearbox 28 is present) or the drive means 7 could be coupled to the connection disc 3 through additional mechanical devices - such as a brake, a clutch, a vibration damper or other or any combination thereof.
[0064] In this embodiment the connection disc 3 is provided with a drive hook and loop fastener part 5 on a drive front surface 4 which is connected to a device hook and loop fastener part 16 arranged on a device back surface 17 of the holding body 9 so that the hook and loop fastener parts 5, 16 are connecting the holding device 8 to the rotational drive 2. In this embodiment the drive hook and loop fastener part 5 is extending substantially across the entire drive front surface 4 of the connection disc 3 and in this embodiment the device hook and loop fastener part 16 is extending substantially across the entire device back surface 17 of the holding body 9 but in another embodiment the drive hook and loop fastener part 5 and / or the device hook and loop fastener part 16 would only extend across a part of the respective surface 4, 17 e.g., if the drive hook and loop fastener part 5 and / or the device hook and loop fastener part 16 was arranged as strips or patches.
[0065] In this embodiment the drive front surface 4 of the connection disc 3 is provided with a number of disc holes 6 extending from the drive front surface 4 and into the connection disc 3 so that the disc holes 6 may be used for dust extraction (disc holes 6 can be seen more clearly in figs. 7 and 9). I.e., in this embodiment the disc holes 6 are through holes but in another embodiment the disc holes 6 could be blind holes.In this embodiment centring pins 18 are protruding from the device back surface 17 of the holding device 8 and in this embodiment each of these centring pins 18 is engaging a disc hole 6 of the disc holes 6 in the drive front surface 4 whereby the holding device 8 is correctly centred on the connection disc 3 and whereby the engagement of the pins 18 in the disc holes 6 may aid in transferring torque across the connection between the holding device 8 and the connection disc 3.
[0066] In this embodiment the centring pins 18 each taper off towards the protruding free end 23 of the centring pins 18 to better guide the holding device 8 to the correct centred position when the holding device 8 is connected to the connection disc 3. However, in another embodiment the centring pins 18 would only taper off a little or the centring pins 18 would not taper off at all - e.g., if separated guiding rails or other was provided to ensure guidance of the holding device 8 to the correct centred position when the holding device 8 is connected to the connection disc 3.
[0067] In this embodiment the abrasion system 1 is formed by providing a rotational drive 2 including a connection disc 3 having a drive front surface 4 which is at least partly provided with a drive hook and loop fastener part 5 and a number of disc holes 6. The rotational drive 2 also comprises drive means 7 for rotating the connection disc 3 continuously in one rotational direction around a single fixed rotational axis. A holding device 8 as described above and in the following is also provided and the centring pins 18 of the holding device 8 are aligned with the relevant corresponding disc holes 6 in the connection disc 3 before the drive hook and loop fastener part 5 of the rotational drive 2 is brought in contact with - and thereby connected to - the device hook and loop fastener part 16 of the holding device 8 so that each of the centring pins 18 is engaging a disc hole 6 of the disc holes 6 in the drive front surface 4 of the connection disc 3.
[0068] In this embodiment all the centring pins 18 are provided with a pin centre hole 29 extending all the way through the centring pins 18 and the holding body 9 so that airextracted through the disc holes 6 can also be extracted through the centring pins 18. However, in another embodiment only some of the centring pins 18 are provided with a pin centre hole 29.
[0069] When the holding device 8 is disc shaped as disclosed in figs. 1-4 the through going pin centre holes 29 will effectively extract dust between some of the abrasive strips 12 to increase the dust extraction effect.
[0070] When the holding device 8 is drum shaped - as disclosed in figs. 6-9 - the through going pin centre holes 29 extract air and dust from the inside of the drum though the open end of the holding body 9 to further increase the dust extraction effect. And to increase the dust extraction effect even further, the side wall of the holding body 9 is in this embodiment also provided with through going side wall holes 30 arranged between neighbouring abrasive strips 12 to enable dust extraction even closer to where the dust is generated. If the holding body 9 is also provided with through going side wall holes 30, the open side of the holding body 9 - i.e., opposite the device back surface 17 - could advantageously not be open or be provided with a lid (not shown) to aid in generating an extraction air flow in through the side wall holes 30.
[0071] Fig. 7 illustrates a drum shaped holding device 8, as seen in an isometric view partly from the back, Fig. 8 illustrates a drum shaped holding device 8, as seen in an isometric view partly from the front, and Fig. 9 illustrates a drum shaped holding device 8, as seen from the back.
[0072] In this embodiment (i.e., in figs. 7-9) the holding body 9 is shown connected to a connection disc 3. I.e., in this embodiment only the connection disc 3 of the rotational drive 2 is shown to enable a better view and understanding of the connection between the holding body 9 and the connection disc 3 of the rotational drive 2.In this embodiment the drum shaped holding body 9 is formed with thirty-two evenly distributed axially undercut grooves 10 formed in an outer surface 11 of the holding body 9, wherein the outer surface 11 in this embodiment is a side surface of the holding body 9. I.e., in this embodiment the longitudinal extent of the undercut grooves 10 is extending substantially parallel with the rotational axis 22 of the holding device 8 - and thereby to the rotational axis of the rotational drive 2 when the holding device 8 is correctly mounted on a connection disc 3 of the rotational drive 2. However, in another embodiment the undercut grooves 10 could be distributed or angled differently - the undercut grooves 10 could e.g., be angled in relation to the rotational axis 22 in an axial direction and / or in an radial direction so that the undercut grooves 10 would not be perpendicular to a diameter of the holding body 9 - and / or the holding body 9 could comprise more axial grooves 10 - such as forty, fifty, sixty or even more - or the holding body 9 could comprise fewer grooves 10 - such as twenty-eight, twenty-three, nineteen or even fewer.
[0073] In this embodiment the drive front surface 4 of the connection disc 3 is provided with a ten small through going disc holes 6 and six larger through going disc holes 6, wherein the six larger through going disc holes 6 corresponds to the six centring pins 18 protruding from the device back surface 17 of the holding device 8 so that the centring pins 18 are each engaging one of the six larger through going disc holes 6. However, in another embodiment the connection disc 3 could comprise more disc holes 6 - such as twenty, thirty, forty or even more - or the connection disc 3 could comprise fewer disc holes 6 - such as twelve, eight, four or even fewer - and likewise the holding device 8 could comprise more centring pins 18 - such as eight, twelve, twenty or even more - or the holding device 8 could comprise fewer centring pins 18 - such as five, four, three or even fewer - as long as the connection disc 3 at least comprises the same number of disc holes 6 as the number of centring pins 18 on the connection disc 3 so that all the centring pins 18 may engage a disc hole 6 in the connection disc 3.In this embodiment all the centring pins 18 are evenly distributed at the same distance from the rotational axis 22 and all the corresponding disc holes 6 in the connection disc 3 are evenly distributed at the same distance from the rotational axis 22 so that both the centring pins 18 and the corresponding disc holes 6 describe a circle. However, in another embodiment the centring pins 18 and the corresponding disc holes 6 would not be evenly distributed and / or the centring pins 18 and the corresponding disc holes 6 would be arranged at varying distances from the rotational axis 22 - such as in a star pattern, oval or other.
[0074] In this embodiment the maximum pin diameter PD of all the centring pins 18 is around 9.5 mm and the maximum disc hole diameter HD of all the corresponding disc holes 6 is around 12 mm and in this embodiment a pin centre circle 25 intersecting the centre of each of the centring pins 18 is around 79.5 mm and a disc hole centre circle 26 intersecting the centre of each of the disc holes 6 is around 73 mm. Thus, in this embodiment the pin outer edge 24 of the centring pins 18 is engaging the disc hole outer edge 27 of the corresponding disc holes 6 in that the tapering part of the pins 18 is pressing against the disc hole outer edge 27 of the corresponding disc holes 6 when the drive hook and loop fastener part 5 and the device hook and loop fastener part 16 are correctly connected to each other. However, in another embodiment the pin centre circle 25 could be smaller than the disc hole centre circle 26 so that an radial inner edge of the centring pins 18 would engage an radial inner edge of the corresponding disc holes 6, or the maximum pin diameter PD would only be slightly smaller than the maximum disc hole diameter HD and the pin centre circle 25 would substantially be the same as the disc hole centre circle 26 so that the pins 18 substantially would be centred in the corresponding disc holes 6 or the pins 18 and disc holes 6 would be arranged differently in relation to each other as long as it is ensured that the pins 18 engages the corresponding disc holes 6 when the drive hook and loop fastener part 5 and the device hook and loop fastener part 16 are correctly connected to each other.Furthermore, in another embodiment the maximum pin diameter PD of at least some of the centring pins 18 and the maximum disc hole diameter HD of at least some of the corresponding disc holes 6 could vary in relation to the other pins 18 and corresponding disc holes 6 and / or the maximum pin diameter PD of the centring pins 18 and the maximum disc hole diameter HD of the corresponding disc holes 6 could be bigger or smaller e.g., depending on the type and make of the rotational drive 2, the diameter (and thereby torque) of the holding device 8, the specific use of the holding device 8 or abrasion system 1 or other.
[0075] In all the figures 1-9 the holding device 8 is shown either as an abrasive disc or an abrasive drum but in another embodiment the holding device 8 could also be formed as an abrasive cone or other depending on the specific use of the holding device 8.
[0076] The invention has been exemplified above with reference to specific examples of abrasion systems 1, rotational drives 2, holding devices 8 and other. However, it should be understood that the invention is not limited to the particular examples described above but may be designed and altered in a multitude of varieties within the scope of the invention as specified in the claims.
[0077] List
[0078] 1. Abrasion system
[0079] 2. Rotational drive
[0080] 3. Connection disc
[0081] 4. Drive front surface
[0082] 5. Drive hook and loop fastener part
[0083] 6. Disc hole
[0084] 7. Drive means
[0085] 8. Holding device
[0086] 9. Holding body10. Undercut groove
[0087] 11. Outer surface
[0088] 12. Abrasive strip
[0089] 13. Abrasive sheet
[0090] 14. Flexible element
[0091] 15. Holding rail
[0092] 16. Device hook and loop fastener part 17. Device back surface
[0093] 18. Centring pin
[0094] 19. First end wall
[0095] 20. Locking part
[0096] 21. Second end wall
[0097] 22. Rotational axis of holding device 23. Protruding free end of centring pin 24. Pin outer edge
[0098] 25. Pin centre circle
[0099] 26. Disc hole centre circle
[0100] 27. Disc hole outer edge
[0101] 28. Gearbox
[0102] 29. Pin centre hole
[0103] 30. Side wall hole
[0104] PD. Maximum pin diameter
[0105] HD. Maximum disc hole diameter
Claims
Claims1. An abrasion system (1) comprisinga rotational drive (2) including• a connection disc (3) having a drive front surface (4), wherein at least a part of said drive front surface (4) is provided with a drive hook and loop fastener part (5) and wherein said drive front surface (4) is provided with a number of disc holes (6) extending from said drive front surface (4) and into said connection disc (3), and• drive means (7) for rotating said connection disc (3) continuously in one rotational direction,said abrasion system (1) further comprising a holding device (8), wherein said holding device (8) includeso a holding body (9) comprising a number of undercut grooves (10) formed in an outer surface (11) of said holding body (9),o abrasive strips (12) comprising an abrasive sheet (13) supported on one side by one or more flexible elements (14), wherein said abrasive sheet (13) and said one or more flexible elements (14) are at one end connected to a holding rail (15), wherein said holding rail (15) is arranged at least partly in one or more of said number of undercut grooves (10) so that said abrasive sheet (13) and said one or more flexible elements (14) are protruding away from said outer surface (11) of said holding body (9),o a device hook and loop fastener part (16) arranged on a device back surface (17) of said holding body (9), wherein said device hook and loop fastener part (16) is connected to said drive hook and loop fastener part (5), ando a number of centring pins (18) protruding from said device back surface (17), wherein each of said number of centring pins (18) is engaging a disc hole (6) of said number of disc holes (6) in said drive front surface (4).
2. An abrasion system (1) according to claim 1, wherein said undercut grooves (10) comprises a first end wall (19) at a first longitudinal end of said undercut grooves (10) and wherein said holding device (8) further comprises a locking part (20) releasably connected to said holding device (8), wherein said locking part (20) forms a second end wall (21) at a second longitudinal end of said undercut grooves (10).
3. An abrasion system (1) according to claim 1 and 2, wherein said number of centring pins (18) are arranged at the same distance from a rotational axis (22) of said holding device (8).
4. An abrasion system (1) according to any of the preceding claims, wherein said number of centring pins (18) each taper off towards a protruding free end (23) of said centring pins (18).
5. An abrasion system (1) according to any of the preceding claims, wherein said holding body (9) is made of a plastic material.
6. An abrasion system (1) according to any of the preceding claims, wherein a longitudinal extent of said undercut grooves (10) is extending substantially parallel with a rotational axis (22) of said holding device (8).
7. An abrasion system (1) according to any of claims 1-5, wherein a longitudinal extent of said undercut grooves (10) is extending substantially perpendicular to a rotational axis (22) of said holding device (8).
8. An abrasion system (1) according to any of the preceding claims, wherein a maximum pin diameter (PD) of said number of centring pins (18) is smaller than a maximum disc hole diameter (HD) of said number of disc holes (6), wherein a pin centre circle (25) intersecting the centre of each of said number of centring pins (18) is bigger than a disc hole centre circle (26) intersecting the centre of each of saidnumber of disc holes (6) so that an pin outer edge (24) of each of the number of centring pins (18) is engaging an disc hole outer edge (27) of each of the number of disc holes (6).
9. An abrasion system (1) according to any of the preceding claims, wherein said one or more flexible elements (14) includes bristles.
10. An abrasion system (1) according to any of the preceding claims, wherein said rotational drive (2) is a rotational sander arranged to continuously rotate said holding device (8) in a single rotational direction around a single fixed rotational axis.
11. An abrasion system (1) according to any of the preceding claims, wherein at least some of said number of centring pins (18) comprise a pin centre hole (29) extending all the way through said centring pins (18) and said holding body (9).
12. A holding device (8) comprising,• a holding body (9) comprising a number of undercut grooves (10) formed in an outer surface (11) of said holding body (9),• abrasive strips (12) comprising an abrasive sheet (13) supported on one side by one or more flexible elements (14), wherein said abrasive sheet (13) and said one or more flexible elements (14) are at one end connected to a holding rail (15), wherein said holding rail (15) is arranged at least partly in one or more of said number of undercut grooves (10) so that said abrasive sheet (13) and said one or more flexible elements (14) are protruding away from said outer surface (11) of said holding body (9),• a device hook and loop fastener part (16) arranged on a device back surface (17) of said holding body (9), wherein said device hook and loop fastener part (16) is arranged for being connected to a drive hook and loop fastener part (5) of a rotational drive (2), and• a number of centring pins (18) protruding from said device back surface (17), wherein each of said number of centring pins (18) is arranged for engaging a disc hole (6) in a drive front surface (4) of said rotational drive (2).
13. A holding device (8) according to claim 12, wherein said holding device (8) is said holding device (8) forming part of said abrasion system (1) according to any of claims 1-11.
14. A method for forming an abrasion system (1), said method comprising the steps of:• providing a rotational drive (2) including a connection disc (3) having a drive front surface (4), wherein at least a part of said drive front surface (4) is provided with a drive hook and loop fastener part (5) and wherein said drive front surface (4) is provided with a number of disc holes (6) extending from said drive front surface (4) and into said connection disc (3), and wherein said rotational drive (2) comprises drive means (7) for rotating said connection disc (3) continuously in one rotational direction,• providing a holding device (8) according to claim 12 or 13,• aligning said number of centring pins (18) with said number of disc holes (6), and• connecting said drive hook and loop fastener part (5) to said device hook and loop fastener part (16) so that each of said number of centring pins (18) is engaging a disc hole (6) of said number of disc holes (6) in said drive front surface (4).
15. A method according to claim 14, wherein said abrasion system (1) is an abrasion system (1) according to any of claims 1-11.