BACKUP PAD CONSTRUCTION AND USE THEREOF

BACKGROUND

Grinding tools are known for use in industrial surface modification applications. They are used with, for example, coated abrasive discs, nonwoven discs or bonded abrasive discs. Grinding tools often couple to abrasive discs through a BUP (“back up pad”) which can help even out a force distribution on an abrasive article.

SUMMARY OF THE INVENTION

The present disclosure relates to BUP (or “backup pad”) and BUP attachment designs that can, for example, interchangeably operate with or without a center post, providing more flexibility and a reduced number of products required by a consumer.

A backup pad assembly is presented that includes a backup pad with a cavity and a centerpost that is coupleable to the backup pad. The backup pad is configured to couple to a tool in a first configuration, without the centerpost, and in a second configuration, with the centerpost.

The above summary is not intended to describe each embodiment or every implementation of the subject matter described herein. Rather, a more complete understanding of the invention will become apparent and appreciated by reference to the following Description of Illustrative Embodiments and claims in view of the accompanying figures of the drawing.

These and other aspects of the invention will be apparent from the detailed description below. In no event, however, should the above summaries be construed as limitations on the claimed subject matter, which subject matter is defined solely by the attached claims, as may be amended during prosecution.

BRIEF DESCRIPTION OF THE DRAWINGS

Throughout the specification, reference is made to the appended drawings, where like reference numerals designate like elements, and wherein:

FIGS. 1A-1B illustrate an electric grinder which may benefit from embodiments herein.

FIGS. 2A-2F illustrate traditional backup pad and attachment configurations.

FIG. 3 depicts an interchangeable backup pad attachment system in accordance with embodiments herein.

FIGS. 4A-4C illustrate centerpost connection mechanisms in accordance with embodiments herein.

FIGS. 5A and 5B illustrate views of alternative connection mechanisms in accordance with embodiments herein.

FIG. 6 illustrates a schematic of an abrading system in accordance with embodiments herein.

FIGS. 7A and 7B illustrate methods of using embodiments described herein.

FIGS. 8A-8F illustrate interchangeable backup pad attachment systems in accordance with embodiments herein.

FIG. 9 illustrates a center post connection mechanism in accordance with embodiments herein.

FIGS. 10A-10C illustrate interchangeable backup pad attachment systems in accordance with embodiments herein.

FIGS. 11A-11D illustrate different embodiments of center post connection mechanisms.

DETAILED DESCRIPTION

The words “preferred” and “preferably” refer to embodiments described herein that may afford certain benefits, under certain circumstances. However, other embodiments may also be preferred, under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the invention.

As used herein and in the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a” or “the” component may include one or more of the components and equivalents thereof known to those skilled in the art. Further, the term “and/or” means one or all of the listed elements or a combination of any two or more of the listed elements.

It is noted that the terms “comprises” and variations thereof do not have a limiting meaning where these terms appear in the accompanying description. Moreover, “a,” “an,” “the,” “at least one,” and “one or more” are used interchangeably herein.

Relative terms such as left, right, forward, rearward, top, bottom, side, upper, lower, horizontal, vertical, and the like may be used herein and, if so, are from the perspective observed in the particular figure. These terms are used only to simplify the description, however, and not to limit the scope of the invention in any way.

Reference throughout this specification to “one embodiment,” “certain embodiments,” “one or more embodiments” or “an embodiment” means that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Thus, the appearances of the phrases such as “in one or more embodiments,” “in certain embodiments,” “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily referring to the same embodiment of the invention. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments.

FIGS. 1A-1B illustrate an electric grinder which may benefit from embodiments herein. Electric grinder 100 includes a motor (not shown in FIGS. 1A-1B) which drives rotation of an abrasive article 120 which is coupled to a backup pad 110. While electric grinders 100 are illustrated, tools using pneumatic or other power sources may also benefit from backup pad (BUP) attachment mechanisms described herein. Additionally, while the depicted rotary grinder is intended to be used handheld, robot-mounted or cart-mounted (e.g., floor sanders) are also within the scope of the present disclosure. Although the presently disclosed accessory attachment assembly is described for rotary tools, systems and methods herein may apply to BUP usage in other tools.

BUP 110 may, generally, comprise a compressible member, in some embodiments, made of a resilient material with a stiffness suitable for the desired application, as known in the art. For example, BUP 110 may be made of resins, constructed through injection molding, such as nylon, polyester, polypropylene, blends thereof or other suitable materials. The shape and size of BUP 110 may also be selected based on a selected abrasive tool 100 or abrasive application.

FIGS. 2A-2F illustrate traditional backup pad and attachment configurations. BUPs 200, 250 are each configured to couple to an abrasive tool, for example by receiving a drive shaft at receiving point 210, which may be threaded or alternate quick change or other suitable attachment system. FIGS. 2A-2C illustrate a traditional BUP 200 with a centerpost 220, while FIGS. 2D-2F illustrate a traditional BUP 250 without a centerpost. Currently, BUPs 200, 250 are offered as separate products, with a centerpost 220 being permanently coupled to a BUP 200, for example using a molded-in design, welding, adhesive, or another suitable method. A centerpost allows for a grinder, such as grinder 100, to operate at a higher operating speed and reducing shifting or “walking” of the abrasive article on the BUP, with centerpost 220 serving to stabilize and center an abrasive disc coupled to BUP 200. However, as centerpost 220 can be seen extending beyond the plane of an abrasive article, as illustrated in FIG. 2C, it can limit the functional angle at which an abrasive tool can approach a worksurface, depending on the height of centerpost 220. Traditionally, centerposts are permanently adhered to a BUP, as illustrated in FIG. 2B, where centerpost 220 is adhered to an attachment side 230 of BUP 200. Attachment side 230, 260 may be configured to engage directly with an abrasive article 240, 270. As illustrated in FIGS. 2B, 2E, attachment side 230, 260 includes protrusions that engage a nonwoven abrasive article 240, 270, through a hook-and-loop-like fastener system. However, other suitable abrasive article attachment systems are envisioned.

Because BUPs are intended to be used for multiple abrasive operations, it is desired to have one BUP that can functionally operate with a centerpost, as illustrated in FIGS. 2A-2C and without a centerpost 2D-2F. A solution is desired that allows for a single BUP to change between a centerpost configuration and a centerpost-free configuration. Such a solution could reduce manufacturing complexity, reduces a number of products a customer needs to purchase, and provides an easy method for switching between configurations.

FIG. 3 depicts an interchangeable backup pad attachment system in accordance with embodiments herein. FIG. 3 illustrates a BUP system 300 that includes a BUP 310, that receives a driveshaft of a tool through aperture 308. BUP 310 also includes a cavity 302 sized to receive a fastener 320. While fastener 320 is illustrated in FIG. 3 as a hex-nut, other suitable removeable fasteners are also envisioned, such as square nuts. For example, in some embodiments, threads are molded into the BUP. In some embodiments, it is desired that cavity 302 and fastener are selected to fit commonly available fasteners, such as hex-nuts, so that specialized components are not required. In other embodiments, fastener is custom-designed to fit cavity 302. In some embodiments, cavity 302 is not circular in shape, or includes at least one corner, such that rotation of a tool drive shaft drives rotation of BUP 310 and fastener 320 at the same rate.

BUP system 300 also includes a removeable centerpost 330. Cavity 302 may include receiving features 304 sized to receive a centerpost feature 332. Centerpost feature 332 may be received by, or couple to, receiving feature 304 and, once received, maintain position such that, when BUP 310 is engaged with a worksurface, centerpost 330 maintains its position with respect to BUP 310. Centerpost feature 332 may engage with receiving feature 304 as a snap, latch, protrusion/aperture pairing, friction, or any other suitable retaining feature, some of which are illustrated herein as examples. However, it is contemplated that other fastening mechanisms may be used.

While only a single feature 332 is illustrated in FIG. 3, this is by example only. It is contemplated that three features 332 may be present on centerpost 330, corresponding to the three receiving features 304 illustrated. For example, two features 332 may be received by two features 304, or four features 332 by four features 304. Or a single feature 332, such as a protrusion along the circumference of post 330 may be received into a receiving slot 304.

In some embodiments, a nonwoven or coated abrasive article may attach to a surface of BUP 310, for example using the 3M Dual Lock™, a molded T-hook system or another suitable system.

In current designs, the axial position of the backup pad is fixed with respect to the rotary shaft of the tool by virtue of the design of the tool from the manufacturer. Although manufacturers may provide a metal washer to be sandwiched in between the backup pad and the tool, such metal washers are designed merely to mitigate heat transfer to prevent seizing of the connected components that might cause the backup pad to fuse to the rotary shaft (and therefore be difficult to unscrew) and to reduce heat transfer into other components of the tool.

FIGS. 4A-4C illustrate centerpost connection systems in accordance with embodiments herein. System 400 includes a threaded connection between a BUP 410, a fastener 420 and centerpost 430. In some embodiments, all three components—BUP 410, fastener 420, and centerpost 430—couple to a threaded drive shaft 402. However, other configurations are expressly contemplated. For example, centerpost 430 may couple directly to BUP 410 and/or fastener 420.

Centerpost 430 includes a removal feature 432, which, in some embodiments, may release a mechanical fastening between centerpost 430 and BUP 410. Removal feature 432 may be sized to receive, for example, a screwdriver, coin, or even a user's fingernail. With sufficient application of torque, a mechanical fastening may be released.

In another embodiment, as illustrated by system 440, centerpost 450 fastens to a BUP using a snap feature 452. Snap feature 452, in the illustrated embodiment, includes a protrusion extending from the BUP which is received by an aperture in centerpost 450. A release mechanism 454 may allow for removal of centerpost 450, for example using a tool to gain leverage and release snap 452. While only one snap feature 452 is illustrated in FIG. 4B, it is contemplated that, in some embodiments, more snaps may be located about a circumference of centerpost 450.

In another embodiment, as illustrated by system 460, a backup pad 470 includes a plurality of snap features 472 that, as illustrated in FIG. 4C, include a protrusion from BUP 470 received by an aperture or cavity of centerpost 480. Snap features 472 may lock into a side of centerpost 480 that opposes BUP 470. As illustrated in FIG. 4C, snap features 472 may allow some sliding or rotation to improve a lock between BUP 470 and centerpost 480. A removal feature 482 may be present on centerpost 480 to allow for easy removal of centerpost 480 from BUP 470.

FIGS. 5A and 5B illustrate views of alternative connection mechanisms in accordance with embodiments herein. FIGS. 5A-1 and 5B-1 illustrate top views (as seen by a user, when on a grinding tool) of a BUP assembly 500, 550, respectively. FIGS. 5A-2 and 5B-2 illustrate perspective views of BUP assemblies 500, 550 with centerposts 520, 570 engaged. FIGS. 5A-3 and 5B-3 illustrate exploded views of BUP assemblies 500 and 550.

BUP assembly 550 includes a centerpost 520 that is received over a fastener 510, such as a threaded fastener. An abrasive article 530 is attached to a receiving side of BUP 500. Fastener 510 is received within a cavity 504. Centerpost 520 may also have a portion 522 that can be received by cavity 504, in a receiving portion 506. Latches, snaps, or other attachment mechanisms are expressly contemplated for coupling portion 522 to receiver 506. Fastener 510 may be integral to BUP 500, or centerpost 520, in some embodiments. However, it may be preferred, for some embodiments, for centerpost 520 to be formed of a different material than fastener 510. For example, fastener 510 may be metal, for resiliency, while centerpost 520 may be plastic, or another material less likely to leave scratches in the worksurface.

A drive shaft of a tool may be received, through BUP 500. BUP 500 may include internal threading to receive a threaded drive shaft tool. However, other suitable coupling mechanisms are possible. Fastener 510 may also have internal threading, such that it is received on the drive shaft with BUP 500 such that, as drive shaft rotates, both fastener 510 and BUP 500 rotate at the same speed with respect to each other. Similarly, centerpost 520 may also have internal threading such that centerpost 520, in some embodiments, couples directly to a driveshaft instead of directly to BUP 500.

BUP assembly 550 is structured similarly to BUP assembly 500, but also includes receiving features 558 shaped to receive corresponding protrusions 578 of a centerpost 570, such that centerpost 570 extends through BUP 550. Fastener 560 is received within cavity 554.

FIG. 6 illustrates a schematic of an abrading system in accordance with embodiments herein. A grinding tool 670 has a motor 672, driven pneumatically or electrically, that drives movement of a drive shaft 674. Grinding tool 670 may have other features 678 as well.

Drive shaft 674 interacts with and rotates at least some components of abrading system 600. A backup pad 620 includes a drive shaft receiver 624, such as internal threading, that couples to backup pad 620 to grinding tool 670.

Backup pad 620 also includes an abrasive article connector 628 that receives an abrasive article 610 on an attachment side of the backup pad 620, the attachment side being opposite a tool side that connects to grinding tool 670.

Backup pad 620 also includes a fastener receiver 626 which couples to a BUP mating feature 642 of a fastener 640. Fastener 640 may assist in maintaining a coupling between backup pad 620 and drive shaft 674 when rotating at high speeds. For example, BUP 620 may include a recess that is shaped to receive fastener 640. For example, fastener 640 may be a hex nut, and fastener receiver 626 may be shaped to receive the hexagon shape of a hex nut.

BUP 620 may also have a centerpost receiver 622 that can receive a BUP connecting feature 652 of a centerpost 650. BUP connecting feature 652 may extend partially into or through BUP 620. BUP connecting feature 652 may couple to centerpost receiver 622 using, for example, snaps, latches, a protrusion fitting to a matching cavity, or any other suitable mechanical fastening. In some embodiments, the mechanical fastening is reversable, either by an applied force, rotation of centerpost 650, or use of a tool. In other embodiments, the mechanical fastening is not easily reversible, or can only be reversed by breaking centerpost 650 or a portion of centerpost 650.

BUP 620 may also have other features 632.

Fastener 640 may have a drive shaft mating feature 644, which couples fastener 640 directly to drive shaft 674. Drive shaft mating feature 644 may include internal threading or other internal features that maintain alignment of fastener 640 with respect to drive shaft 674 when drive shaft 674 rotates. However, in some embodiments, fastener 640 does not couple directly to drive shaft 674, and only directly couples to BUP 620. Fastener 640 may also have a centerpost mating feature 646, in some embodiments, that allows fastener 640 to directly couple to a fastener connecting feature 654 of a centerpost 650. However, in other embodiments, fastener 640 does not directly couple to centerpost 650. Fastener 648 may have other features 648.

Abrading system 600 may also have a centerpost 650 that can be optionally used when higher rotational speeds are needed for an abrasive operation. Centerpost 650 may connect to BUP 620, using a BUP connecting feature 652, in some embodiments. Centerpost 650 may also, or alternatively, couple to fastener 640, in some embodiments, using fastener connecting feature 654. Centerpost 650 may also, or alternatively, couple to drive shaft 674, in some embodiments, using a drive shaft connecting feature 656. Centerpost 650 may also have other features 658, such as a removal feature, which may include a tool-receiving slot, in some embodiments.

FIGS. 7A and 7B illustrate methods of using embodiments described herein. Methods 700 and 750 illustrate methods in which a configuration of a grinding system is changed from a first configuration to a second configuration. In some embodiments, methods 700 and 750 are reversible such that, for example, a device can go from operating with a centerpost, to operating without a centerpost, and then back to operating with a centerpost. However, in some embodiments, a centerpost may be a single-use article such that removal may damage it such that reuse is not possible, such as breaking or twisting a connecting feature.

Method 700 is a method of converting an abrading system from a first configuration 710, with a centerpost 712, to a second configuration, without a centerpost. In the first configuration 710, a centerpost is coupled to a BUP system, for example either directly to a backup pad, to a fastener, to a drive spindle, or another component such that, when the drive shaft is rotating, centerpost also rotates.

An abrasive article may need to be removed, as indicated in block 720, in order to remove a centerpost. However, in some embodiments it is expressly contemplated that an abrasive article is directly coupled to a backup pad, e.g. through a hook and loop, 3M Dual Lock™ system, or other suitable system, such that a centerpost can be removed without disturbing the abrasive article.

The centerpost is removed, as indicated in block 730. The centerpost may be reusably removed, as indicated in block 724. For example, the centerpost may be held in place mechanically, using a snap or latch. Removing the centerpost may include rotating the centerpost or applying force or torque to mechanically undo the snap or latch. Removing the centerpost may be toolless, as indicated in block 732 such that a user can remove the centerpost with their fingers or hand, in some embodiments. In other embodiments, the centerpost may be removeable with application of torque or force by a tool. The centerpost may be coupled to a BUP system without adhesive, as indicated in block 734. In other embodiments, the centerpost may be a single-use centerpost, as indicated in block 722 held in place with single-use adhesive, as indicated in block 734. Other methods of removal are contemplated, as indicated in block 736. In other embodiments, the centerpost is a single-use centerpost, as indicated in block 722, with a mechanical component that cannot be removed without breaking the centerpost. Removing a centerpost, in block 730, requires breaking the centerpost. It is expressly envisioned that a BUP system, such as that envisioned in FIG. 6, may include a BUP, a fastener, and a number of single-use centerposts.

In embodiments where an abrasive article needs to be removed to access the centerpost, as indicated in block 720, the abrasive article may be replaced, as indicated in block 740. Alternatively, when an abrasive article needs to be replaced, the old abrasive article may be removed, in block 720, and a new abrasive article may be applied, as indicated in block 740.

Method 750 is a method of converting a BUP system from a first configuration 760, without a centerpost 762, to a second configuration 790, with a centerpost in place. The centerpost may be permanently coupled to the BUP system, or may be removeably coupled to the BUP system.

In some embodiments, it may be necessary to remove an abrasive article, as indicated in block 770. Some abrasive articles have a centerhole, as illustrated in FIG. 2C, configured to fit around a centerpost. Other abrasive articles, as indicated in FIG. 2B, do not have a centerhole. To switch from configuration 760 to configuration 790 may require removing an abrasive article without a centerhole and replacing it with an abrasive article compatible with a centerpost. However, at least some abrasive articles may be configured to operate in both first configuration 760 and second configuration 790. For example, as illustrated in FIG. 5B-1, a centerpost may extend through receiving slots in a BUP, and may also extend through corresponding apertures in an abrasive article (not shown). In such embodiments, it may only be necessary to remove an abrasive article, as indicated in block 770, when replacing a used abrasive article with a new abrasive article.

A centerpost is applied, in block 780. The centerpost may be applied using a snap mechanism, as indicated in block 792, a latch mechanism, as indicated in block 794, or another suitable mechanism, as indicated in block 796, such as a sliding lock, for example. Other suitable mechanical fastening methods are envisioned.

In some embodiments, the centerpost is a single-use centerpost that is applied permanently to a BUP. For example, in some embodiments, an adhesive is used to make the centerpost application permanent. In other embodiments, the centerpost snaps or latches into place such that removal breaks a component of the centerpost, such as a protruding portion.

In some embodiments, the centerpost is applied in a nonpermanent, releaseable manner, such that, for example, method 700 may be used next. The centerpost may be applied and/or removed toollessly, as indicated in block 782, for example with a latch 794 that slides or rotates into place. The centerpost may be applied without adhesive, as indicated in block 784, so that it can be removed and reused. Other application methods are also envisioned, as indicated in block 786.

FIGS. 8A-8F illustrate centerpost attachment systems in accordance with embodiments herein. FIGS. 8A and 8B illustrate a BUP system 810 where a centerpost 806 is received by a cavity 802, and an abrasive article is received by an attachment surface 804.

FIG. 8C illustrates another centerpost attachment system 830, that includes a BUP 822 with a keyhole 824 that receives a correspondingly shaped key 828 in a centerpost 826. While an X-lock design is illustrated in FIG. 8C, it is expressly contemplated that other designs, such as a “T” or “+” are expressly contemplated.

While a centerpost has been described herein as being inserted through a centerhole, or through apertures, of an abrasive article, it is expressly contemplated that an abrasive article may attach to an attachment surface of a backup pad 842 over a centerpost 844, which may couple to a backup pad and form a flat, substantially planar surface, as illustrated in FIG. 8D.

FIG. 8E illustrates a schematic of a wedge locking system. System 870 removeably couples a centerpost 876 to a backup pad 872. Illustrated in FIG. 8E is an embodiment where a wedge 854 is a separate component from both backup pad 858 and centerpost 852. However, this is for simplicity in explanation only. It is expressly contemplated that either or both of backup pad 858 or centerpost 852 have a wedge that provides a biasing force to keep the components coupled during use.

As illustrated in FIG. 8E, centerpost 852 is received into a cavity 862 of backup pad 858, as illustrated by arrow 864. Cavity 862 is slightly larger than a diameter of centerpost 852, allowing for centerpost to be easily inserted and removed. To increase tension and hold centerpost in place, a wedge component 854 is separately inserted and fastened to backup pad 858 using fastener 856. Fastener 856 is illustrated as a screw, however other suitable fasteners are contemplated. As wedge 854 is fastened and moves in the direction of arrow 866, a combined diameter of centerpost 852 and wedge 854 increases, until it is greater than a diameter of cavity 862, which then causes a biasing force in the direction of arrow 868. Any of centerpost 852, wedge 854 or backup pad 858 may be made of a material with some compressibility to accommodate the full insertion of wedge component 854.

In FIG. 8F, a spring latch system is presented for a backup pad system 870. Backup pad 872 has a coil 874 or O-ring within a groove that is configured to receive a post 876 of a centerpost 876. However, while the spring latch is illustrated as part of the backup pad 872 in FIG. 8F, it is expressly contemplated that the components could be switched, with a receiving post extending from a backup pad that receives a spring latch and coil within centerpost 876.

In FIG. 8F, a spring latch 872 with a coil 874 or O-ring within a groove is configured to fit over a post 876 to form a connection system 870. The spring latch 872 may be part of a centerpost that fits over a post 876 that is part of a BUP. Alternatively, the spring latch 872 may be part of a BUP that receives a post 876 of a centerpost.

FIG. 9 illustrates a center post connection mechanism in accordance with embodiments herein. FIG. 9 illustrates an embodiment of a center post 900. Center post 900 includes two movable features 910 that, when a force 920 is applied, can move in direction 922. Center post 900 also includes one or more side walls 930. Each sidewall 930, in some embodiments, has a smaller diameter, or the same diameter, as the inner diameter of an abrasive disc. Features 910, are angled with respect to a surface of center post 900, such that an effective diameter of features 910 is larger than an inner diameter of an abrasive disc.

FIGS. 10A-10C illustrate interchangeable backup pad attachment systems in accordance with embodiments herein. FIG. 10A illustrates a center post 1002 coupled to a backup pad 1010. FIG. 10B illustrates an image of center post 1002 coupled to backup pad 1010. Backup pad 1010 has a DUAL-LOCK™ surface that receives an abrasive article. However, it is expressly contemplated that other coupling features between backup pad 1010 and an abrasive article are possible. FIG. 10C illustrates an abrasive article 1030 coupled to a backup pad (not shown). Center post 1004 is substantially coplanar with a surface of abrasive article 1030. However, it is expressly contemplated, that in some embodiments center post 1004 may be depressed with respect to abrasive article 1030, or may extend further from a backup pad than abrasive article 1030. Because an effective diameter of center post 1040 is larger than the inner diameter of abrasive article 1030, center post 1004 maintains a position of abrasive article 1030 on a backup pad.

FIGS. 9-10 illustrate a center post configuration, where a center post has a wider effective diameter than an inner diameter of an abrasive article due to the movable features and one or more side walls. However, it is expressly contemplated that other center post designs may also be suitable.

FIGS. 11A-11D illustrate different embodiments of center post connection mechanisms. FIG. 11A illustrates a center post configuration 1110, which is similar to that shown in FIG. 9-10. Movable features include an angled exterior wall with respect to a backup pad surface. In contrast, FIG. 11B illustrates a center post 1120 with movable features with exterior walls perpendicular to a backup pad surface. It is also expressly contemplated that more or fewer movable features may be suitable. For example, FIG. 11C illustrates a center post 1030 with three movable features and three side walls. Movable features of center post 1030 may be slanted with respect to a backup pad surface, or perpendicular with respect to a backup pad surface. FIG. 11D illustrates a center post 1040 that includes no movable features, but achieves a similar effect using two slanted side walls.

It is expressly contemplated that other suitable configurations are possible in other embodiments.

Other centerpost attachment mechanisms are expressly contemplated. For example, as discussed above, the centerpost may couple directly to a drive shaft of a grinding tool. Alternatively, or additionally, the centerpost may contain threading that couples to internal threading on the BUP such that the centerpost can be screwed onto, and off of, the centerpost. Additionally, the BUP may include a molded slot that receives a protrusion of the centerpost. Alternatively, the molded slot may be part of the centerpost that receives a protrusion from the BUP.

Additionally, while centerpost is described herein as a separate component from the fastener, it is expressly contemplated that a single machined component may replace the two components, such that a single machined or casted component serves as the centerpost and is coupled into the BUP.

Mechanical fastening systems are described herein for coupling a centerpost to a BUP. However, it is also contemplated that the centerpost and/or the BUP may include a magnetic component either in addition to or instead of a mechanical fastening. For example, a protrusion on either the BUP or the centerpost may be magnetically attracted to a cavity in the centerpsot or the BUP.

Additionally, an interface may exist, in some embodiments, between the centerpost and the BUP, such as a series of flats, polygons or cylinders with an interference fit.

It is also expressly contemplated that additional fastening mechanisms may be utilized, such as additional mechanical fasteners.

While a threaded attachment is shown and described as the main coupling mechanism between a drive shaft and components of a BUP assembly, other secure connections could be used within the scope of the present disclosure. For example, attachment between the BUP, fastener and/or centerpost may be carried out by a quick-connect mechanism. The centerpost may also be directly connected to a shaft of a robotic tool. A quick-connect mechanism may comprise, for example, a bayonet or other twist-lock cooperation. Linear or other non-rotating quick-connects may also be used, such as spring-loaded ball-and-socket connections or hex-shank quick connections.

Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It will be apparent to those skilled in the art that various modifications and variations can be made to the method and apparatus of the present invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention include modifications and variations that are within the scope of the appended claims and their equivalents.

The assembly may be implemented such that it includes a fastener that fits within the cavity.

The assembly may be implemented such that the backup pad includes an abrasive article attachment surface.

The assembly may be implemented such that the attachment surface includes a dual lock system or a hook and loop system.

The assembly may be implemented such that the backup pad includes a centerpost receiving feature that receives a corresponding backup pad mating feature of the centerpost.

The assembly may be implemented such that the backup pad includes a driveshaft attachment mechanism.

The assembly may be implemented such that the centerpost includes a driveshaft attachment mechanism.

The assembly may be implemented such that the fastener includes a driveshaft attachment mechanism.

The assembly may be implemented such that the centerpost receiving feature is a cavity, and the backup pad mating feature includes a protrusion.

The assembly may be implemented such that the centerpost receiving feature is a protrusion and the backup pad mating feature includes a cavity.

The assembly may be implemented such that the centerpost is removeably coupleable to the backup pad.

The assembly may be implemented such that the coupling includes a snap.

The assembly may be implemented such that the coupling includes a latch.

The assembly may be implemented such that the coupling includes a key and keyhole.

The assembly may be implemented such that the backup pad includes a cavity with a wedge. A wedge diameter, in combination with a centerpost diameter, is greater than a diameter of the cavity.

The assembly may be implemented such that the centerpost includes a wedge, the backup pad includes a cavity. A wedge diameter, in combination with a centerpost diameter, is greater than a diameter of the cavity.

The assembly may be implemented such that it includes a wedge component configured to be fastened in place such that, on a first side, the wedge contacts the centerpost and, on a second side, the wedge contacts the backup pad.

The assembly may be implemented such that the coupling includes a spring latch.

The assembly may be implemented such that the coupling is a toolless coupling.

The assembly may be implemented such that the coupling is adhesive free.

The assembly may be implemented such that the coupling is a mechanical coupling.

The assembly may be implemented such that the centerpost includes a tool receiving slot such that the centerpost is uncoupleable from the backup pad.

A method of converting a backup pad assembly from a centerpost configuration to a centerpost-free configuration is presented. The method includes uncoupling a centerpost from a backup pad. The coupling is a mechanical coupling. The method also includes attaching an abrasive article to the backup pad. The backup pad is coupled to a drive shaft of a powered tool. The backup pad is operable, coupled to the powered tool, in both the centerpost configuration and the centerpost-free configuration.

The method may be implemented such that the centerpost is a single-use centerpost, such that uncoupling the centerpost from the backup pad renders it unusable.

The method may be implemented such that uncoupling the centerpost breaks or deforms a portion of the centerpost.

The method may be implemented such that the backup pad includes a cavity, and further including a fastener that fits within the cavity.

The method may be implemented such that the backup pad includes an abrasive article attachment surface.

The method may be implemented such that the centerpost, when coupled to the backup pad, is substantially planar with the attachment surface.

The method may be implemented such that it includes removing a used abrasive article. The used abrasive article covers the centerpost.

The method may be implemented such that the backup pad includes a centerpost receiving feature that receives a corresponding backup pad mating feature of the centerpost. Uncoupling the centerpost includes uncoupling the backup pad mating feature from the centerpost receiving feature.

The method may be implemented such that the backup pad includes a driveshaft attachment mechanism.

The method may be implemented such that the centerpost includes a driveshaft attachment mechanism.

The method may be implemented such that the fastener includes a driveshaft attachment mechanism.

The method may be implemented such that the centerpost receiving feature is a cavity, and the backup pad mating feature includes a protrusion.

The method may be implemented such that the centerpost receiving feature is a protrusion and the backup pad mating feature includes a cavity.

The method may be implemented such that the coupling includes a snap.

The method may be implemented such that the coupling includes a latch.

The method may be implemented such that the coupling includes a key and keyhole.

The method may be implemented such that the backup pad includes a cavity with a wedge. A wedge diameter, in combination with a centerpost diameter, is greater than a diameter of the cavity.

The method may be implemented such that the centerpost includes a wedge, the backup pad includes a cavity. A wedge diameter, in combination with a centerpost diameter, is greater than a diameter of the cavity.

The method may further include a wedge component configured to be fastened in place such that, on a first side, the wedge contacts the centerpost and, on a second side, the wedge contacts the backup pad.

The method may be implemented such that the coupling includes a spring latch.

The method may be implemented such that the coupling is a toolless coupling.

The method may be implemented such that the coupling is adhesive free.

The method may be implemented such that the coupling is a mechanical coupling.

The method may be implemented such that the centerpost includes a tool receiving slot such that the centerpost is uncoupleable from the backup pad.

A method of converting a backup pad assembly from a centerpost-free configuration to a centerpost configuration is presented that includes coupling a centerpost to a backup pad. The centerpost has a backup pad connecting feature that couples to a centerpost receiving feature of the backup pad. The method also includes applying an abrasive article to an attachment surface of the backup pad. The backup pad is coupled to a drive shaft of a powered tool. The backup pad is operable, coupled to the powered tool, in both the centerpost configuration and the centerpost-free configuration.

The method may be implemented such that the centerpost is a single-use centerpost.

The method may be implemented such that uncoupling the centerpost breaks or deforms a portion of the centerpost.

The method may be implemented such that the backup pad includes a cavity, and further including a fastener that fits within the cavity.

The method may be implemented such that the backup pad includes an abrasive article attachment surface.

The method may be implemented such that the centerpost, when coupled to the backup pad, is substantially planar with the attachment surface.

The method may further include removing a used abrasive article. The used abrasive article covers the centerpost.