Sander Flex Pad for Rotary Floor Sander

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of US provisional patent application 63/412,283 filed September 30, 2022, which is hereby incorporated by reference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

Not Applicable.

APPENDIX

Not Applicable.

BACKGROUND OF THE INVENTION

FIELD OF THE INVENTION

[0001] The present invention relates to rotary floor sanders, and more particularly to a sander flex pad for rotary floor sanders that allows the use of the rough grit sandpaper to provide a final finish without scratches when refinishing a floor.

RELATED ART

[0002] For years now professional floorers and do it yourselfers have been finishing their hardwood floors in their homes with equipment that consists of machines like industrial grade seven inch rotary floor sander edgers that use a sander pad. This machine performs the task of sanding the floor at the base of a wall where the larger floor sanders cannot reach. This machine will take the top layer of wood surface from the floor to expose the undamaged unvarnished wood to later refinish for a greater appearance. During the process of sanding the floor the process has multiple steps requiring different amounts of stiffness in the sander pad and the coarseness of the sandpaper. [0003] The first step in edging along the base of a wall is to use the seven inch floor sander edger with a rotating tool that is usually rigid enough to allow for the abrasive surface that is applied to the tool to remove greater amounts of wood when pressure is applied. This process removes the surface varnish previously applied to the floor and also deep surface abrasions in the floor. The second step is to replace the rigid sanding pad for one that is more flexible to sand finer details. The process of removing the sander pad from the rotary sander and replacing it with a different pad can be a complicated and time-consuming one.

[0004] US Patent 11,027,393, which is hereby incorporated by reference, provides rotary floor sander having a sander plate that allows the changing of the sander pad from a stiffer pad to a more flexible pad with a simple adjustment that is quick and easy by using the claimed adjustable sander pad assembly. A sander flex pad is mounted over the sander plate and under the sandpaper pad. The sander flex pad 10 of the present invention is suitable for the device of US Patent 11,027,393.

[0005] Typically, at least two grits are used in sanding floors. Rough grit, about 50 grit, is used initially and then fine grit is used to provide a smooth finish that doesn't show scratches. The present invention is a sander flex pad that has been modified with at least one cut that terminates before the peripheral edge of the disc, and allows the rough grit sand paper to be used to do the final sanding without leaving scratches. The sander flex pad is attached to a rotary floor sander over the sander plate and under the sandpaper pad.

RELATED ART

[0006] U.S. Patent 3,111,792, which is hereby incorporated by reference, discloses a sandpaper backing disc, e.g., as sander flex pad, for rotary floor sanders that has been modified to have a plurality of arcuate slots with trailing ends that split the peripheral edge of the disc. The slots form resilient fingers that flex independently. For the arcuate slots in used, the outer ends are disposed in the trailing end and the inner ends are leading.

[0007] Neither of the above-cited art references disclose the present invention.

SUMMARY OF THE INVENTION

[0008] The present invention is a sander flex pad suitable for use with a rotary floor sander, wherein the sander flex pad comprises a flat circular disc and a peripheral edge, and wherein the sander flex pad has more than one cut through the metal sander flex pad, where the cut terminates before splitting the peripheral edge. The circular peripheral edge remains unbroken and intact.

[0009] Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, arc intended for purposes of illustration only and are not intended to limit the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:

[0011] FIG. 1 is a bottom perspective view of the sander flex pad of the invention.

[0012] FIG. 2 is a top view of the sander flex pad of the invention.

[0013] FIG. 3 is a top perspective view of the sander flex pad of the invention.

[0014] FIG. 4 is a left side perspective view. The right side perspective view is identical.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.

[0016] As shown in FIGs. 1 - 4, the sander flex pad 10 is a flat circular disc 11. The disc does not contain bumps or ridges. It can be made out any robust material, but preferably stainless steel, and more preferably spring stainless steel which is about 0.035 inches thick. Typically, the sander flex pad is seven (7) inches in diameter. The center opening 15 on the sander flex pad is typically 2 to 2.5 inches and is used to mount the sander flex pad on the circular floor sander.

[0017] On the sander flex pad are screw openings 14 that are used with screws to mount the pad onto the circular floor sander. There are usually about 4 to 8 screw openings 14, and are spaced circumferentially around the center opening 15 to provide balance when rotating. Spaced around the sander flex pad are two (2) or more cuts 12. The cuts 12 are non-circular. The cuts are not circular holes. The number of cuts 12 is preferably from about 2 to 12. More preferably there are from about 4 to 10 cuts 12, and most preferably about 6. The cuts 12 are evenly spaced around the flex pad to create balance when the pad is rotating. The cuts can be made with any type of cutting tool, but preferably the cut is made with a water jet. The cuts penetrate through the metal completely and are not merely surface grooves. Further, the cuts do not cut through the center opening 15 or the peripheral edge 16 of the sander flex pad. Preferably, the cuts are spaced about 2.0 to 0.25 inch from the center opening and about 2.0 to 0.25 inch from the peripheral edge when a 7 inch sander flex pad is used.

[0018] In a preferred embodiment, the cuts 12 are arcuate. In a preferred embodiment, for a seven inch sander flex pad, the cuts are from about 1.75 to 2.25 inches long and are in a repeating pattern, so that, for a counter clockwise rotation from the floor perspective, as opposed to the operator perspective, the leading end 17 of the cut is closer to the peripheral edge and the trailing end 18 is closer to the center opening. Preferably, the leading end of the cut is from about 1.50 to 2.0 inches from the center opening. The trailing edge is from about 0.75 to 1.25 inches from the center opening. Preferably, the arc is made with an about 3 to 4 inch radius. In most preferred embodiment, there are six cuts evenly spaced around the sander flex pad in a repeating pattern.

Preferably at each end of the cut is a small circular opening 13 terminating each end of the cut to prevent stress cracks from radiating out of end of the cut. Preferably, the small circular opening is about 0.10 to 0.30 inches in diameter. The width of the cut is preferably narrow, from about 0.100 to 0.010 inch, but could be as large as 0.25 inch.

[0019] In an embodiment, the sander flex pad 10 is mounted with the bottom facing the floor. In that configuration, the leading edge 17 becomes the trailing edge and the trailing end 18 becomes the leading edge.

[0020] In a preferred embodiment of the invention, the sander flex pad 10 is mounted on a rotary sander (not shown). In a more preferred embodiment, the rotary sander having the sander flex pad 10 mounted on it has sandpaper (not shown) mounted on the flex pad 10 and is suitable for sanding a floor.

[0021] The embodiments were chosen and described to best explain the principles of the invention and its practical application to persons who are skilled in the art. As various modifications could be made to the exemplary embodiments, as described above with reference to the corresponding illustrations, without departing from the scope of the invention, it is intended that all matter contained in the foregoing description and shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.