WO2019138324A1

WO2019138324A1 - Spring mounted abrasive article for floor maintenance

Info

Publication number: WO2019138324A1
Application number: PCT/IB2019/050138
Authority: WO
Inventors: Lijun Zu; James L. ERICKSON; Dean S. Holmes; John E. MOUNTAIN
Original assignee: 3M Innovative Properties Company
Priority date: 2018-01-09
Filing date: 2019-01-08
Publication date: 2019-07-18

Abstract

A floor cleaning and polishing assembly comprising a round driver that can be mounted to a rotary floor machine. The driver includes an attachment mechanism for attaching the driver to the rotary floor machine and a plurality of openings for attaching a plurality of individual brushes to the driver. At least one of the plurality of brushes includes a brush base and bristles, the bristles comprising moldable polymeric material and abrasive particle additives. At least one of the brushes is removably mounted to the driver using a spring attachment mechanism.

Description

SPRING MOUNTED ABRASIVE ARTICLE FOR FLOOR MAINTENANCE

Background

[0001] Concrete, terrazzo and other hard surfaces are often used in both residential and commercial flooring applications because they provide a robust and economical flooring solution. In some instances, such a floor may be left unfinished, partially finished, or completely finished, depending on the desired level of gloss. In some commercial settings, such as bulk retailers or home improvement stores where flooring experiences high volumes of heavy foot and machine traffic, the store prefers not to apply floor finishes or sealers due to the expense and time required for continued upkeep of the finishes or sealers.

[0002] Currently, non-woven abrasive floor pads or rigid abrasive systems (such as the Diamabrush sold by Diamabrush LLC of Madison Heights, Michigan) are used for floor finishing or cleaning.

Nonwoven floor pads can be an expensive and inefficient solution because they are not as durable when used on a bare concrete surface. Rigid abrasive systems may last longer, but have a tendency to yield inconsistent or uneven results in the floor surface. Rigid abrasive systems also often miss low spots due to the rigidity of the construction.

[0003] Several patents mention the problem of effectively cleaning flooring. One such patent is United States Patent 5,679,067“Molded Abrasive Brush” to Johnson et al. This patent describes an abrasive brush having a plurality of bristles unitary with the backing. These brushes can be mounted to a backing, which is in turn mounted to a driver if used for a floor cleaning machine.

[0004] United States Patent 8,206,201“Working System Using Brush Tool” to Fioratti_discusses a brush tool that can have bristles of different sizes and can be mounted to a tool head of a tool machine.

[0005] There still exists opportunities for improved systems for cleaning, resurfacing and finishing floors.

Summary

[0006] The present invention provides significant improvements over existing solutions for finishing concrete, terrazzo or other hard floor surfaces. The present invention provides a durable cleaning device that does not wear as quickly as a non-woven floor pad and provides increased durability for finishing rough floor surfaces. The present invention further allows for reduced waste and increased economy through providing for the individual replacement of bristle brushes. Some aspects of the present invention also provide for a way to better clean or finish rough or uneven floors through the increased flexibility of individual brushes. Floors can be uneven due to an unfinished surface, grout lines, or gaps between tiles. The present disclosure provides a way to better clean these low spots in a floor. The present disclosure further provides an advantage over other bristle brush constructions by increasing gloss through daily floor cleaning, particularly when the brush bristles contain fine grade abrasive particles.

[0007] In one instance, the present disclosure includes a floor cleaning and polishing assembly comprising a round driver that can be mounted to a rotary floor machine. The driver includes an atachment mechanism for ataching the driver to the rotary floor machine. The driver includes a plurality of openings for ataching a plurality of individual brushes to the driver. At least one of the plurality of brushes comprises: a brush base and bristles, the bristles comprising moldable polymeric material and abrasive particle additives. The at least one of the brushes is removably mounted to the driver using a spring atachment mechanism.

[0008] In another instance, the present disclosure includes a brush for atachment to a floor cleaning driver. The brush comprises a brush base, and bristles. The bristles comprise moldable polymeric material and abrasive particle additives. At least one of the brushes is removably mounted to the driver using a spring atachment mechanism.

[0009] In another instance, the present disclosure includes a floor cleaning and polishing assembly comprising a round driver that can be mounted to a rotary floor machine. The driver comprises an atachment mechanism for ataching the driver to the rotary floor machine and a plurality of openings for mechanically ataching a plurality of individual brushes to the driver. At least one of the plurality of brushes comprises a brush base and bristles. The bristles comprising moldable polymeric material and abrasive particle additives wherein the at least one of the brushes is removably mounted directly to the driver.

[0010] In some instances, the abrasive particles comprise diamond particles.

[0011] In some instances, the abrasive particles comprise at least one of: aluminum oxide, silicon carbide, diamond, precision shaped grains, agglomerates.

[0012] In some instances, the abrasive particles have a median particle size in the range of 0.1 microns to 1,000 microns.

[0013] In some instances, the abrasive particles have a median particle size in the range of 1 microns to 10 microns.

[0014] In some instances, the perimeter of the at least one of the plurality of brushes is circular.

[0015] In some instances, the perimeter of the at least one of the plurality of brushes is wedge-shaped.

[0016] In some instances, the bristles have a conical shape, wherein the circumference of the base of the bristle is larger than the circumference of the tip of the bristle.

[0017] In some instances, the plurality of brushes is in the range of three brushes to fifty brushes.

[0018] In some instances, the spring constant is in the range of 800 N/m to 25,000 N/m.

[0019] In some instances, the spring constant of the spring atachment mechanism is in the range of 1,000 N/m to 10,000 N/m.

[0020] In some instances, the bristle height is in the range of 5 mm to 25 mm.

[0021] In some instances, at least one of the plurality of brushes can be removed from the driver and replaced. [0022] In some instances, the bristles on each of the plurality of brushes can simultaneously contact a floor surface when pressure is applied to the driver, even when the length of the bristles varies between brushes.

[0023] In some instances, the spring constant of the spring attachment mechanism is in the range of 1,000 N/m to 10,000 N/m.

[0024] In some instances, the brush base is molded such that it is integral with the bristles.

[0025] In some instances, the diameter of the bristles is in the range of about 0.75mm to 3.0 mm.

[0026] In some instances, a single brush may be attached to a driver by two spring attachment mechanisms.

Brief Description of the Drawings

[0027] The invention may be more completely understood when considered with the following detailed description in connection with the accompanying drawings, in which:

[0028] Figure 1 shows a bottom view of a driver with a plurality of brushes mounted to the driver.

[0029] Figure 2 shows a side view of a driver with a plurality of brushes mounted to the driver, showing the spring mounting of one of the brushes in a compressed position.

[0030] Figure 3 shows a driver laying on its back side, showing the spring mounting of one of the brushes in a compressed position.

[0031] Figure 4 shows a bottom view of a driver with a plurality of wedge-shaped brushes mounted to the driver.

[0032] Figures 5A-5B show round brushes.

[0033] Figures 6A-6B show wedge-shaped brushes.

[0034] Figure 7 shows the spring mounting mechanism for a round brush.

[0035] Figure 8 shows the spring mounting mechanism for a wedge-shaped brush.

[0036] Figure 9 is a weight versus displacement plot for Example 1.

[0037] The embodiments shown and described herein may be utilized and structural changes may be made without departing from the scope of the invention. The figures are not necessarily to scale. Like numbers used in the figures refer to like components. However, the use of a number to refer to a component in a given figure is not intended to limit the component in another figure labeled with the same number.

Detailed Description

[0038] Figure 1 shows a bottom view of a driver 100 with a plurality of bristle brushes 104 mounted to the driver. The driver 100 shown in Figure 1 is round, and can be mounted to a rotary floor cleaning machine using a mounting mechanism on the back side of the driver. The mounting mechanism is often specific for the rotary floor cleaning machine used. Examples of mounting mechanisms consistent with the present disclosure include pegs, clips, springs, or magnetic systems. Mounting mechanisms can be made from a variety of materials, and are typically a combination of metal and plastic. Examples of rotary floor cleaning machines that driver 100 can be attached to include floor cleaning machines made by Tennant Co. of Minneapolis, Minnesota; Nilfisk, Inc. of Brondby, Denmark; and Diversey, Inc. of Elmwood Park, New Jersey. Drivers can be purchases from any of these companies, or from Malish Brush Corporation of Mentor, Ohio.

[0039] Driver 100 can be made from a variety of materials. Is some instances, driver 100 may be wood. In other instances, driver 100 may be a metal such as aluminum, wood, or a molded plastic.

Driver 100 may have a size compatible for use with a cleaning machine. For example, in Figure 1, driver 100 has a 50.8 cm (20 inch) diameter and is approximately 1.5 cm to 2.5 cm in thickness. Driver 100, as shown, has opening 102 in the center, which can be used to accommodate water flow, or provide additional clearance for an attachment mechanism. Drivers consistent with the present disclosure may have a range of diameters, thicknesses, and attachment mechanisms to meet the size constraints of different cleaning machines.

[0040] Driver 100 includes a plurality of openings 110 for attaching a plurality of individual brushes 104 to the driver. Figure 1 shows a total of twenty brushes 104 mounted to the driver 100 at regular intervals. However, any number of brushes 104 in the range of 3 brushes to 50 brushes may be mounted to the driver 100. While driver 100 also has a number of smaller holes as shown in Figure 1, those are a function of the original driver design and are not contemplated to be used for mounting brushes in the specific prototype shown in Figure 1.

[0041] Brushes 104 as shown in Figure 1 are round. However, brushes 104 may have a variety of shapes, including wedge, square, triangular, trapezoidal, oval and irregular. Brushes 104 each comprise a plurality of bristles 106, the bristles comprising moldable polymeric material and abrasive particle additives. In some instances, the brushes 104 may be made as an integral mold. In other instances, bristles 106 may individually or as groups, and may be mounted to a backing to form a brush 104. As shown in Figure 1, brushes 104 have concentric rings of bristles 106 with a section 108 without bristles in the center.

[0042] Brushes 106 are removably mounted to driver 100 by using a spring attachment mechanism, or a removable attachment mechanism as described in further detail herein.

[0043] Figure 2 shows a side view of an assembly 200 including driver 205 with a plurality of brushes 210 including bristles mounted to the driver 205 with a spring attachment mechanism 220. As shown in Figure 2, several of the brushes, including brush 212, are in a compressed position, pressed against work surface 240. Brush 216 is in an extended position, in contrast to brush 212. The spring mechanism 220 allows brushes to conform to surface level irregularities when pressed against an uneven surface. Specifically, the spring in the spring attachment mechanism 220 can compress for high spots, or extend for low spots. Further, Spring attachment mechanism 220 allows each brush to contact a surface even in a situation where the bristles on one brush are more worn down and thus shorter than the bristles on a second brush, or when there are multiple brushes 210 with different bristle heights on the same driver 205. This can be particularly useful when a single brush has been worn and is replaced with a new brush. Even though the new brush may have longer bristles than other brushes on the driver, each of the brushes can simultaneously contact the same surface because the height difference between the brushes is absorbed by the spring mechanism 220. This can result in more efficient use of such an assembly and decreased waste that can occur when an entire assembly 200 is replaced because some portions of it are worn out.

[0044] Brushes 210 are mounted to driver 205 through holes 214. To mount brushes 210 to driver 205, the brushes 210 are first attached to a backup pad 224 as shown in Figure 2. Brushes 210 can optionally be molded with integral threading to allow easy attachment to a backup pad 224. The backup pad 224 and brush 210 are then mounted to driver 205 using a spring attachment mechanism 220. As pictured in Figure 2, spring attachment mechanism 220 includes a hex socket head and partially threaded bolt in combination with a compression spring. The bolt is placed through the hole 214 in driver 205, and threaded through the compression spring. The threaded end of the bolt is screwed into the threading in the back up pad 224. Without the compression spring, the bolt would be able to move relatively freely back and forth through hole 214. However, the compression spring suspends the brush 210 at a distance from the bottom surface of the driver 205. The brush 210 can be moved toward driver 205 by the brush 210 encountering sufficient force to compress the spring. Because the brushes are each individually suspended in the manner as shown in Figure 2, the brushes can be compressed independently of each other to allow use of the assembly on an uneven surface. Brush 212 is an example a brush in a compressed position. Brush 216 is an example of a brush in a released position.

[0045] While Figure 2 shows one particular example of a spring attachment mechanism, other spring attachment mechanisms may be used consistent with the present disclosure. For example, a spring attachment mechanism may be internal to the back-up pad or the brush construction. In another instance, a back-up pad or brush may have a bolt or screw extending from it such that the bolt or screw twists into the driver pad. Other variations on a spring attachment mechanism will be apparent to one of skill in the art upon reading the present disclosure. In some instances consistent with the present disclosure, a spring may not be included in the attachment mechanism, but the individual brushes are still individually removable and replaceable.

[0046] Figure 3 shows a floor cleaning and polishing assembly 300 including a driver 305 laying on its back side, showing the spring attachment mechanism 320 of one of the brushes 312 in a compressed position. Driver 305 has multiple brushes 310 secured to the driver 305 using spring attachment mechanisms 320. Brush 312 is in a compressed position such that bolt 316 is pressed partially through the hole in driver 305, and spring 314 is in a compressed position.

[0047] Figure 4 shows a bottom view of an assembly including driver 400 with a plurality of wedge- shaped brushes 420 mounted to the driver 400. Brushes 420 include a plurality of bristles 424. Brushes 420 are mounted to driver 400 using the two concentric rings of holes in driver 400. Hole 416 is part of the inner ring of holes and hole 405 is part of the outer ring of holes. Each wedge brush 420 is removably attached to driver 420 using an attachment mechanism through one of the holes in the inner ring of holes, and one of the holes in the outer ring of holes.

[0048] Brushes 420 are an example of a wedge shape brush that can be used consistent with the present disclosure. The narrower end of brush 420 has a width Wl of 2.2 cm. The wider end of brush 420 has a width W2 of 3.8 cm. Brush 420 has a length L of 10.5 cm. While these are examples of dimensions of a wedge-shaped brush, other wedge shaped brushes may be used consistent with the present disclosure.

[0050] Figures 5A-5B show round brushes. Figure 5A shows a perspective view of a round brush 500. Round brush 500 has a central area 510 without bristles, two inner circles of bristles 512 and four outer circles of bristles 514, forming a total of 194 bristles. The bristles 512, 514 are integrally molded with brush 500 as shown in Figure 5. Inner bristles 512 are 1 27cm (0.5 in) long with a constant diameter of 1.88 mm (0.074 in). Outer bristles 514 have a conical shape. As shown in Figure 5A, bristles 114 are 1.27 cm (0.50 in) long and tapered from 2.54 mm (0.10 in) diameter at the root to 1.27 mm (0.05 in) diameter at 80% of the length from root to tip, and had a diameter of 1.27 mm (0.05 in) for the remainder of the length to tip.

[0049] Figure 5B shows a bottom view of a round abrasive brush 500. Abrasive brush 500 has a diameter D of 5 cm (2 in), and a thickness of 2.54 mm (0.1 in.). Abrasive brush 500 has six concentric rings of bristles, including two inner rings 512 and four outer rings 514.

[0050] While Figures 5 A and 5B show brushes with particular shapes, sizes, number of bristles, and bristle lengths, a wide range of parameters could be used in consistent with the present disclosure. For example, in some instances, there may be bristles in the center of the brush. In some instances, all the bristles may be the same shape and size. In other instances, the bristles may have more than two different shapes or sizes. The bristles may have a cylindrical shape, a conical shape, wherein the circumference of the base of the bristle is larger than the circumference of the tip of the bristle, or another shape altogether. Bristle height may range from, for example, 5 mm to 25 mm. The diameter of the bristles may range from about 0.75 to 3.0 mm.

[0051] Brushes consistent with the present disclosure may include moldable polymeric material and abrasive particles. The type and size of abrasive particles can be chosen based on the desired level of abrasion or polishing. In some instances, the abrasive particles include at least one of: diamond particles, aluminum oxide, silicon carbide, diamond, precision shaped grains, agglomerates.

[0052] The abrasive particles may have a variety of sizes. For example, they may have a median particle size in the range of 0.1 to 1,000 microns. In another instances, they may have a median particle size in the range of 1 micron to 10 microns.

[0053] Types of moldable polymeric material that may be used consistent with the present disclosure include, for example, a thermoplastic polymer, or a thermoplastic elastomer. [0054] Examples of thermoplastic polymers include polycarbonate, polyetherimide, polyester, polyethylene, polysulfone, polystyrene, polybutylene, acrylonitrile-butadiene-styrene block copolymer, polypropylene, acetal polymers, polyurethanes, polyamides, and combinations thereof.

[0055] Thermoplastic elastomers are generally the reaction product of a low equivalent weight polyfunctional monomer and a high equivalent weight polyfunctional monomer, wherein the low equivalent weight polyfunctional monomer has a functionality of at most about 2 and the equivalent weight of at most about 300 and is capable of polymerization of forming a hard segment (and, in conjunction with other hard segments, crystalline hard regions or domains) and the high equivalent weight polyfunctional monomer has a functionality of at least about 2 and an equivalent weight of at least about 350 and is capable on polymerization of producing soft, flexible chains connecting the hard regions or domains. Examples of thermoplastic elastomers include segmented polyester thermoplastic elastomers, segment polyurethane thermoplastic elastomers, segmented polyamide thermoplastic elastomers, blends of thermoplastic elastomers and thermoplastic polymers, and ionomeric thermoplastic elastomers. Other examples of suitable moldable polymeric materials can be found United States Patent 6,126,533 to Johnson et al.

[0056] Figures 6A-6B show wedge-shaped bristle brushes. Figure 6A shows a perspective view of brush 600. Figure 6B shows a bottom view of brush 600. Brush 600 has a wedge shape with a width Wl of 2.2 cm (0.875 in), a width W2 of 3.8 cm (1.50 in) and has a length F of 10.5 cm (4.125 in). Brush 600 has 440 bristles extending from one major surface. The bristles as shown in Figures 6A and 6B are each

1.5 cm (0.59 in) long, 2.3 mm (0.090 in) diameter at the root and 1.0 mm (0.040 in) diameter at tip. The

5.5 mm (0.375 in) long portion of the bristle adjacent tip is cylindrical. Other wedge brush shapes, sizes and constructions, and bristle shapes, sizes and constructions will be apparent to one of skill in the art upon reading the present disclosure.

[0057] Figure 7 shows the floor cleaning and polishing assembly 700 with a closer view of spring attachment mechanism 720 for a round bristle brush 710. Brush 710 is mounted to a back-up pad 730 using threading threaded protrusion in brush 710 that can be screwed into a threaded opening in back-up pad 730. Spring attachment mechanism 720 includes bolt 724 that is threaded through the hole 706 in driver 705. Bolt 724 is then threaded through spring 726 and screwed into the back-up pad 730. Washer 722 is placed between the surface of driver 705 and spring 726. Washer 722 serves to distribute the pressure of the spring coming into contact with the driver 705. While a threaded protrusion in brush 710 is one way to attach brush 710 to a back-up plate 730, other mechanisms for attaching brush 710 to a back-up pad 730 will be apparent to one of skill in the art upon reading the present disclosure. For example, brush 710 may be attached to back up pad 730 using a hook and loop attachment system.

Alternately, friction may be used to hold brush 710 in place through inclusion of a slot in back up pad 730 that the back surface of brush 710 can slide into. Other ways to attach brush 710 to back-up pad 730 include a snap system, adhesive, or a magnetic attachment mechanism. Further, in another instance, brush 710 and back-up plate 730 may be integrally constructed so that bolt 724 can screw directly into the integral construction.

[0058] Spring 726 may have a variety of spring constants. In some instances the spring constant may be in the range of 800 N/m to 25,000 N/m. In some instances the spring constant of the spring attachment mechanism is in the range of 1,000 N/m to 10,000 N/m. In other instances, the spring constant may be in the range of 3,000 N/m to 4,000 N/m.

[0059] Figure 8 shows the floor cleaning and polishing assembly 800 with a closer view of spring attachment mechanisms 820 for a wedge-shaped brush 810. In Figure 8, hook and loop is adhered to brush 810 and used to attach brush 810 to aluminum backing plate 830. Backing plate 830 in turn has two sets of threading into which a partially threaded bolt 826 can be screwed.

[0060] Wedge shaped brush has two spring attachment mechanisms 820. To attach the brush to driver 805, partially threaded bolt 826 is inserted through hole 806 in driver 805. Bolt 826 is inserted through spring 824 and screwed into the threading in aluminum back-up plate 830. Springs 824 serve to suspend brush 810 a maximum distance from the surface of driver plate 805, while still allowing brush 810 to be compressed towards driver plate 805 when the force on the brush exceeds the spring force.

[0061] The mounting configurations of the present disclosure allow a single brush to be removed and replaced when that particular brush experiences excessive wear.

[0062] Additionally, the spring mounting system allows the bristles on multiple brushes to simultaneously contact a floor surface when pressure is applied to the driver, even when the length of the bristles varies between brushes, or when the floor surface is uneven.

Examples

[0063] Molded bristle pads were fabricated with various shapes and abrasives. These pads were mounted on a pad driver with and without springs. The pads were tested for polishing performance on smooth surfaces.

[0064] These examples are merely for illustrative purposes only and are not meant to be limiting on the scope of the appended claims. All parts, percentages, ratios, etc. in the examples and the rest of the specification are by weight, unless noted otherwise.

Table. Materials and sources.

Preparation of Vitreous Bonded Diamond Agglomerates

1. 3um Diamond Agglomerates

The slurry was prepared as follows. About 50 grams of dextrin (a temporary starch binder obtained under the trade designation“Stadex 235 Dextrin” from Tate & Lyle, Lafayette, IN.) was dissolved in about 1100 grams of deionized water by stirring using an air mixer With a Cowles blade. Next, about 800 grams of 3um micrometer diamond powder (available from World Wide Super Abrasives, Boynton Beach, FL.) was added to the slurry. Intermediate slurry was high shear mixed with a rotor stator mixer for 10 minutes. Slurry was filtered with a lOmicron cartridge filter. Next, about 800 grams of milled glass frit (obtained under the trade designation“SP1086” from Specialty Glass, Inc. Oldsmar, FL.) was added to the solution. The glass frit had been milled prior to use to a median particle size of about 2.5 micrometers. Slurry was high shear mixed with a rotor stator mixer for 10 minutes. The slurry was spray dried using a rotary wheel spray dryer (obtained under the trade designation MOBILE MINOR UNIT” from Niro Inc.). The spray dryer inlet temperature was set at about 200° C., and the rotary wheel set at about 35,000 rpm. The slurry was pumped into the nozzle inlet at a pump speed flow rate setting of 3-4. The outlet temperature of the spray dryer varied from 90 - 95° C. during the spray drying of the slurry. The plurality of precursor agglomerate abrasive grains was collected at the spray dryer outlet.

The spray dried precursor agglomerate grains were mixed with about 60% by weight of 3 micrometer white aluminum oxide (obtained under the trade designation“PWA3” from Fujimi Corporation, Tualatin, OR.), based on the Weight of the plurality of precursor agglomerate grains, and heated in a furnace in air. The heating schedule was as follows: 2 C./min. increase to 400°C., 1 hour hold at 400°C., 2°C./min increase to 750°C. 1 hour hold at 750°C., and l0°C./min. decrease to 35° C.

After heating, the agglomerate abrasive grains were sieved through a 63 micrometer mesh screen.

2. 9um Diamond Agglomerates

The same procedures as above were used, except:

About 800 grams of milled glass frit (obtained under the trade designation“SP1086” from Specialty Glass, Inc. Oldsmar, FL.) was added to the solution after the dextrin. Next, 9 micrometer diamond powder (available from Sandvik Hyperion, Boynton Beach, FL.) was added to the slurry. Slurry was high shear mixed with a rotor stator mixer for 10 minutes. The spray dryer inlet temperature was set at about 150° C., and the rotary wheel set at about 27,500 rpm. The slurry was pumped into the nozzle inlet at a pump speed flow rate setting of around 4. The outlet temperature of the spray dryer varied from 75° C. during the spray drying of the slurry.

After heating, the agglomerate abrasive grains were sieved through a 106 micrometer mesh screen.

Formulation and Preparation of Test Samples

Molded abrasive bristle brush were fabricated by injection molding according the method disclosed in US 5,679,067 (Johnson et al.). The formulations used for the Examples 1-8 are reported in Table 1. Listed are the polymer components used, and the type and amount of abrasive particles. All compositions are reported as weight ratios or percent by weight. Prior to molding, the polymer components were placed in aNelmor Company Model G810 Ml plastic granulator and ground until the components passed through the sifter mesh and were dried at 65°C (l50°F) for 4 hours in an air dryer; abrasives were then added and mixed in a barrel for about 30 minutes.

Table 1 : Example Formulations

Example 1

Example 1 used a mold similar to the 2” 3M ROLOC Bristle Disc (Figures 1 and 2 of US 5,679,067 (Johnson et al.). The base of the abrasive brushes had a diameter of 5 cm (2 in), and a thickness of 2.54 mm (0.1 in.). The abrasive brush had 194 integrally molded bristles on outer 4 circles and 60 bristles on inner 2 circles. Each bristle on outer circles was 1.27 cm (0.50 in) long and tapered from 2.54 mm (0.10 in) diameter at the root to 1.27 mm (0.05 in) diameter at 80% of the length from root to tip, and had a diameter of 1.27 mm (0.05 in) for the remainder of the length to tip. Each bristle on inner circles was l.27cm (0.5 in) long and had a diameter of 1.88 mm (0.074 in). Each abrasive brush included an integrally molded threaded stud as the attachment means according to U.S. Pat. No. 3,562,968 (Johnson et al.). A 20-inch Pad Driver with magnetic hub was purchased from Tennant Co. Minneapolis, MN.

Twenty (20) holes were drilled at an equal intervals on a circle which is about 9 inches from the center, and another 20 holes were drilled at an equal intervals on a circle which is about 5.5 inches from the center. Ten (10) of the molded abrasive brushes with 3M ROLOC Bristle Disc Back-up pads were mounted on the 20 inch pad driver using HEX socket head shoulder 5/16” X 1 ¼” bolt and Gardner Spring Inc. Tulsa, OK (36114G) Compression Spring. The springs had an estimate spring constant in the range of 3400 - 3800 N/m. The spring constant was given by Hooke’s law. Three springs were compressed on LLOYD materials testing instrument at 4 different compression distance, the

corresponding weight was recorded. The weight and displacement data were plotted, and the spring constant is the slope of the straight line Weight vs. Displacement plot as shown in Figure 9. The bolt and spring system allows each individual brush to move up and down. This enables the height-adjustability feature. There were 5 brushes on the outer circle and 5 brushes on the inner circle.

Example 2

Example 2 was fabricated using the same mold and formulation as Example 1. The only difference is that Example 2 has 20 abrasive brushes mounted on the 20 inch pad driver using same type of bolts and springs. 10 brushes on the outer circle and 10 brushes on the inner circle.

Example 3

Example 3 was fabricated using the same mold as Example 1. The formulation for Example 3 was listed in Table 1. 10 of the molded abrasive brushes were mounted on the 20 inch pad driver using same type of bolts and springs. 5 brushes on the outer circle and 5 brushes on the inner circle.

Example 4

Example 4 was fabricated using the same mold and formulation as Example 3. The only difference is that Example 4 has 20 abrasive brushes mounted on the 20 inch pad driver using same type of bolts and springs. 10 brushes on the outer circle and 10 brushes on the inner circle.

Example 5

Example 5 was fabricated using the same mold and formulation as Example 3. The only difference is that Example 5 has 40 abrasive brushes mounted on the 20 inch pad driver using same type of bolts and springs. Twenty (20) brushes on the outer circle and 20 brushes on the inner circle.

Example 6

Example 6 was fabricated using the same mold as Example 1. The formulation for Example 6 was listed in Table 1. Twenty (20) of the molded abrasive brushes were mounted on the 20-inch pad driver using same type of bolts and springs. Ten (10) brushes on the outer circle and 10 brushes on the inner circle.

Example 7

Example 7 was fabricated using the same mold as Example 1. The formulation for Example 6 was listed in Table 1. Twenty (20) of the molded abrasive brushes were mounted on the 20 inch pad driver using same type of bolts and springs. 10 brushes on the outer circle and 10 brushes on the inner circle.

Example 8

In example 8 brushes were injection molded using a different mold design (Figure 11 of US 5,679,067 (Johnson et al . )) . The base was a generally wedge-shaped polygon, 10.5 cm (4.125 in) long by 3.8 cm (1.50 in) wide at one end and 2.2 cm (0.875 in) wide at the opposite end. Extending from one major surface were 440 bristles each 1.5 cm (0.59 in) long, 2.3 mm (0.090 in) diameter at the root and 1.0 mm (0.040 in) diameter at tip. The 5.5 mm (0.375 in) long portion of the bristle adjacent tip was cylindrical. The back of the base is flat. The formulation is same as Example 8. Each wedge-shaped brush was attached to an aluminum plate using 3M hook and loop. 12 of the wedge-shaped brushes were mounted on the 20-inch pad driver using same bolts and springs at an equal intervals towards the outer circle. Each brush/aluminum plate used two bolts and two springs.

Comparative Example 1

Comparative Example 1 was fabricated using the same mold and formulation as Example 3. 20 of the molded abrasive brushes were screwed/secured on the 20 inch pad driver without springs. 10 brushes on the outer circle and 10 brushes on the inner circle.

Comparative Example 2

3M General Purpose Floor Brush 53 (3M Company, St. Paul, MN)

Table 2 Examples

Test Methods

Each example was tested on a bare concrete floor using Tennant T300 auto scrubber machine, Tennant Co. Minneapolis, MN. Rhopoint IQ 20/60 meter (available from IMBOTEC Group Company) was used to measure Gloss and DOI value of the concrete floor surface.

Bare concrete floor, area 1 was prepared using 3M TRIZACT HX Gold, Red and Blue discs (3M Company St. Paul, MN) using the following procedures (6 passes of each set of TRIZACT discs using Tennant T300 auto scrubber machine). After preparation, initial gloss and DOI of the concrete floor was measured. Initial Gloss was in the range of 4 ~ 5 and initial DOI was in the range of 40 ~ 50. The concrete floor was divided into multiple lanes and each lane was scrubbed using Examples 2, 4, 6, 7, and CE2 for 16 passes, respectively. Each of these Examples were chosen because they included 20 circular brushes. The gloss and DOI of the concrete floor surface was measured again using Rhopoint IQ 20/60 meter after 16 passes of scrubbing. The Gloss and DOI data DOI before and after scrubbing was listed in Table 3. All Examples have gloss increase and Example 6 with 3um diamond/glass agglomerates shows the highest gloss increase. All examples show reduction in DOI and Example 7 with 9um diamond/glass agglomerates is the worst. The 3M Floor Brush 53 (CE2) shows minimum DOI reduction when the initial DOI of the concrete floor is in the range of 40-50.

Another area of concrete floor, area 2 was prepared using exact same process as above. However, the initial gloss was in the range of 11-13 and the initial DOI was in the range of 70-80. The concrete floor was divided into multiple lanes and each lane was scrubbed using Examples 1- 5, 8, CE1, and CE2 for 16 passes, respectively. The gloss and DOI of the concrete floor surface was measured again using Rhopoint IQ 20/60 meter after 16 passes of scrubbing. The Gloss and DOI data before and after scrubbing was listed in Table 4. The effect of number of mounted bristle brushes on the performance was studied. The data in Table 4 shows that the more mounted brushes, the higher gloss increase, but the higher reduction in DOI. Examples with and without springs show similar performance on smooth surface. The springs are expected to help on an uneven surface, to allow brushes to adjust to different heights to simultaneously reach different surface levels on an uneven floor or surface. Example 8 with wedge-shape bristle brushes show higher gloss increase and smaller reduction in DOI, compared with Examples 4 and CE1 with 20 Roloc bristle brushes. This might be due to the thinner tips on the bristles. When the initial DOI of the concrete floor is high in the range of 70-80, 3M floor brush 53 (CE2) showed a significant reduction in DOI.

Tables 5 and 6 show the calculated contact pressure of the various Examples when used with a 100 lbs load. The contact pressure was calculated by:

F mg

P

A A

P - Pressure

F - Force

A - Contact Area

m - Mass

g - Acceleration of gravity

Table 5 Pressure calculation when tip of the bristles contact floor surface

Table 6 Pressure calculation when root of the bristles contact floor surface

The following are exemplary embodiments according to the present disclosure: Item 1. A floor cleaning and polishing assembly comprising:

a round driver that can be mounted to a rotary floor machine, the driver comprising: an attachment mechanism for attaching the driver to the rotary floor machine; a plurality of openings for attaching a plurality of individual brushes to the driver; wherein at least one of the plurality of brushes comprises: a brush base, and bristles, the bristles comprising moldable polymeric material and abrasive particle additives;

wherein the at least one of the brushes is removably mounted to the driver using a spring attachment mechanism.

Item 2. The assembly of item 1, wherein the abrasive particles comprise diamond particles.

Item 3. The assembly of item 1, wherein the abrasive particles comprises at least one of: aluminum oxide, silicon carbide, diamond, precision shaped grains, agglomerates.

Item 4. The assembly of item 1, wherein the abrasive particles have a median particle size in the range of 0.1 microns to 1,000 microns.

Item 5. The assembly of item 4, wherein the abrasive particles have a median particle size in the range of 1 microns to 10 microns.

Item 6. The assembly of item 1, wherein the perimeter of the at least one of the plurality of brushes is circular.

Item 7. The assembly of item 1, wherein the perimeter of the at least one of the plurality of brushes is wedge-shaped.

Item 8. The assembly of item 1, wherein the bristles have a conical shape, wherein the circumference of the base of the bristle is larger than the circumference of the tip of the bristle.

Item 9. The assembly of item 1, wherein the plurality of brushes is in the range of 3 brushes to fifty brushes.

Item 10. The assembly of item 1, wherein the spring constant is in the range of 800 N/m to 25,000 N/m.

Item 11. The assembly of item 10, wherein the spring constant of the spring attachment mechanism is in the range of 1,000 N/m to 10,000 N/m. Item 12. The assembly of item 1, wherein the bristle height is in the range of 5 mm to 25 mm.

Item 13. The assembly of item 1, wherein the at least one of the plurality of brushes can be removed from the driver and replaced.

Item 14. The assembly of item 1, wherein the bristles on each of the plurality of brushes can simultaneously contact a floor surface when pressure is applied to the driver, even when the length of the bristles varies between brushes.

Item 15. A brush for attachment to a floor cleaning driver, the brush comprising:

a brush base; and

bristles, the bristles comprising moldable polymeric material and abrasive particle additives;

Item 16. The brush of item 15, wherein the spring constant of the spring attachment mechanism is in the range of 1,000 N/m to 10,000 N/m.

Item 17. The brush of item 15, wherein the brush base is molded such that it is integral with the bristles.

Item 18. The brush of item 15, wherein the length of the bristles is in the range of 5 mm to 25 mm.

Item 19. The brush of item 15, wherein the diameter of the bristles is in the range of about 0.75mm to 3.0 mm.

Item 20. The brush of item 15, further comprising a second spring attachment mechanism.

Item 21. A floor cleaning and polishing assembly comprising: a round driver that can be mounted to a rotary floor machine, the driver comprising:

an attachment mechanism for attaching the driver to the rotary floor machine;

a plurality of openings for mechanically attaching a plurality of individual brushes to the driver;

wherein at least one of the plurality of brushes comprises: a brush base and bristles, the bristles comprising moldable polymeric material and abrasive particle additives; wherein the at least one of the brushes is removably mounted directly to the driver.

Claims

What is claimed is:

1. A floor cleaning and polishing assembly comprising:

2. The assembly of claim 1, wherein the abrasive particles comprise diamond particles.

3. The assembly of claim 1, wherein the abrasive particles comprises at least one of:

aluminum oxide, silicon carbide, diamond, precision shaped grains, agglomerates.

4. The assembly of claim 1, wherein the abrasive particles have a median particle size in the range of 0.1 microns to 1,000 microns.

5. The assembly of claim 4, wherein the abrasive particles have a median particle size in the range of 1 microns to 10 microns.

6. The assembly of claim 1, wherein the perimeter of the at least one of the plurality of brushes is circular.

7. The assembly of claim 1, wherein the perimeter of the at least one of the plurality of brushes is wedge-shaped.

8. The assembly of claim 1, wherein the bristles have a conical shape, wherein the

circumference of the base of the bristle is larger than the circumference of the tip of the bristle.

9. The assembly of claim 1, wherein the plurality of brushes is in the range of 3 brushes to fifty brushes.

10. The assembly of claim 1, wherein the spring constant is in the range of 800 N/m to 25,000 N/m.

11. The assembly of claim 10, wherein the spring constant of the spring attachment mechanism is in the range of 1,000 N/m to 10,000 N/m.

12. The assembly of claim 1, wherein the bristle height is in the range of 5 mm to 25 mm.

13. The assembly of claim 1, wherein the at least one of the plurality of brushes can be

removed from the driver and replaced.

14. The assembly of claim 1, wherein the bristles on each of the plurality of brushes can

simultaneously contact a floor surface when pressure is applied to the driver, even when the length of the bristles varies between brushes.

15. A brush for attachment to a floor cleaning driver, the brush comprising:

a brush base; and

16. The brush of claim 15, wherein the spring constant of the spring attachment mechanism is in the range of 1,000 N/m to 10,000 N/m.

17. The brush of claim 15, wherein the brush base is molded such that it is integral with the bristles.

18. The brush of claim 15, wherein the length of the bristles is in the range of 5 mm to 25 mm.

19. The brush of claim 15, wherein the diameter of the bristles is in the range of about

0.75mm to 3.0 mm.

20. The brush of claim 15, further comprising a second spring attachment mechanism.

21. A floor cleaning and polishing assembly comprising: a round driver that can be mounted to a rotary floor machine, the driver comprising:

an attachment mechanism for attaching the driver to the rotary floor machine;

a plurality of openings for mechanically attaching a plurality of individual brushes to the driver; wherein at least one of the plurality of brushes comprises: a brush base and bristles, the bristles comprising moldable polymeric material and abrasive particle additives;

wherein the at least one of the brushes is removably mounted directly to the driver.