US3641611A

US3641611A - Brush construction

Info

Publication number: US3641611A
Application number: US863779A
Authority: US
Inventors: Arthur T Schofield
Original assignee: Manufactures Brush Co
Current assignee: Milwaukee Brush Manufacturing Co Inc
Priority date: 1969-10-06
Filing date: 1969-10-06
Publication date: 1972-02-15
Anticipated expiration: 1989-02-15
Also published as: DE2049087A1; GB1316325A

Abstract

Rotary brushes formed with brush components comprising a bundle of bristle material bound and tightly compacted at one end by a uniformly corrugated metal band, the other end of such bristle bundle extending from the corrugated band to form a composite generally circular brush face, including rotary end brushes and rotary wheel brushes of substantially unitary design and also of a plurality of end-to-end interlocking annular brush elements; further including the foregoing brushes with plastic holder portions; and, further including the foregoing brushes with convexly curved elastomeric collars, such as O-rings encircling the bristles inside the holders.

Description

United States Patent Schofield Feb. 15,1972

[541 BRUSH CONSTRUCTION [72] Inventor: Arthur T. Schofield, Brecksville, Ohio [73] Assignee: The Manulacturers Brush Company,

Cuyahoga, Ohio 221 Filed: Oct. 6,1969 [21 Appl.No.: 863,779

1,928,990 10/1933 Barnettet al. ..l5/190 Peterson 15/180 Wiseman 15/180 Williamson et al. ..15/183 Primary Examiner-Peter Feldman Attomey-McCoy, Greene & Howell [57] ABSTRACT Rotary brushes formed with brush components comprising a bundle of bristle material bound and tightly compacted at one end by a uniformly corrugated metal band, the other end of such bristle bundle extending from the corrugated band to form a composite generally circular brush face, including rotary end brushes and rotary wheel brushes of substantially unitary design and also of a plurality of end-to-end interlocking annular bl'LlSh elements; further including the foregoing brushes with plastic holder portions; and, further including the foregoing brushes with convexly curved elastomeric collars, such as O-rings encircling the bristles inside the holders.

24 Claims, 10 Drawing Figures mtufturmsmra I v 3.641.611

' INVENTOR. ARTHUR T. SCHOFIELD ATTORNEY PATENTEUFEBYSIQYZ I I 3.641 .6l1

SHEET 2 OF 2 8 32 FIG. 9

FIG. IO

INVENTOR. ARTHUR T SCHOFIELD BY Ma 60, Gaeene a awell ATTORNEYS BRUSH CONSTRUCTION BACKGROUND AND SUMMARY OF INVENTION This invention relates to brush construction wherein a rigid corrugated metal band is employed to tightly bind bristle material to form a bristle cartridge for mounting in a holder to form a power-driven industrial rotary end brush and other rotary brushes. 7

In the manufacture of power-driven industrial rotary brushes, it is essential to mount the bristle material securely in the bristle holder to prevent the bristle. material from loosening and flying out of the holder in use.

A number of different techniques have been employed to this end. One construction has been to wrap the bristles about an anchor ring ,or other retaining member in the base of the holder. Another construction has been to hold the bristles with a quantity of solder in the base of the holder cup.

Nevertheless, a variety of problems have been encountered in constructions of these types, including the weakening of bristles undergoing a sharp flex at the retaining member, loss of temper by bristles subjected to soldering temperatures, uneven fill distribution, and the difficulty and expense of subsequently trimming the brush to a true flat face.

I have found that I can overcome these problems by enclosing one end of a bundle of brush bristle material with a deformable metal band and deforming that band inwardly at regularly spaced intervals to form uniform corrugations therein, thereby tightly compacting one end of the bristle bundle in a uniformly corrugated metal band so that the other end of the bristle bundle extends from the band to provide a composite generally circular brush face.

In the past, persons have bound brush bristle material into bundles or tufts of various sizes and shapes prior to mounting in various holders, as may be seen by reference to US. Pat. Nos. 2,202,292; 2,421,647; 3,312,993; and 3,380,098.

Nevertheless, crimped metal binders have not been considered practical for quality power-driven industrial rotary end brushes, (end brushes are constructed with a plurality of parallel bristles mounted in a cup-shaped holder so that they extend generally parallel to the axis of brush rotation but flare radially under the centrifugal force of power operation) since a brush face formed from bristle material held in this manner conforms roughly to the shape of the crimped binder resulting in an irregular brush face. An irregular brush face is generally undesirable in quality power-driven industrial rotary end brushes because those portions of the bristle bundle that depart from or protrude out of a generally circular blllSII face configuration are increasingly subject to long bristle fracture and can cause uneven brushing and/or objectionable vibration.

I have overcome these difficulties with the brush construction of the present invention, which, although it does not provide a perfectly circular brush face, provides a brush face which is generally circular. The degree to which my brush face departs from a perfect circle is relatively small and I have found it has insignificant consequences in operation, primarily because relatively few bristles are involved and they are evenly distributed in a balanced generally circular configuration about the brush face perimeter. At the same time, I have found that the same banded bristle bundle (bristle cartridge hereafter) which is satisfactory for an industrial power driven rotary end brush according to the present invention can be used as a component for a great variety of different rotary brushes with various beneficial results so that it serves as an interchangeable constructional module for the construction of a varied line of brush types by an industrial brush manufacturer, reducing the need for a plurality of difierent types of bristle binding equipment and operations and lending simplicity to the manufacturing procedures for such brushes.

Another advantage of the present invention is that the bristle ends may be registered prior to binding and, upon binding,

I will maintain their alignment to form a relatively smooth brush face which requires relatively little or no finish grinding or trimming by comparison to other bristle-binding techniques.

A further advantage is that the binder may be made of a relatively high thennal conducting metal, such as copper, which acts as a heat sink to conduct heat away from the point where the bristles emerge from the holder, so that bristle cartridges so bound may be used to advantage in rotary brushes having holders, collars and/or bridles of plastic or other relatively low melting point materials.

A still further advantage is that the bristle cartridge is otherwise well suited for construction of brushes of the type wherein a smooth convexly curved reinforced elastomeric collar encirclesthe bristles where they emerge from the bristle holder so that very durable brushes may be constructed as disclosed in my copending US. Pat. application Ser. No. 763,238.

Furthermore, the bristle cartridge is otherwise well suited to mounting in plastic holders since the metal binder relieves stresses that would otherwise be taken up by the plastic holder and because the cartridge may be mounted in the holder with epoxy adhesive or the like, rather than with solder or by some other substance which would be deleterious or inappropriate to the plastic.

These and other advantages, and objects of this invention, will be apparent to persons skilled in the art from the following description, claims and drawings. To theaccomplishment of the foregoing and related ends, the invention then comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and annexed drawing setting forth in detail certain illustrative embodiments of the invention, these being indicative however of but a few of the various ways in which the principles of the present invention may be employed.

BRIEF DESCRIPTION OF DRAWING In the annexed drawing:

FIG. 1 is an elevational partially sectioned view of a rotary end brush according to my invention, said brush having a corrugated metal-banded bristle bundle held in a metal cupshaped holder.

FIG. 2 is a transverse section taken on the line 2-2 of FIG. 1.

FIG. 3 is a transverse section taken on the line 3-3 of FIG. 1.

FIG. 4 is an exploded view of the brush shown in FIG. 1.

FIG. 5 is an elevational partially sectioned view of another embodiment of the present invention comprising a rotary end brush having a corrugated metal-banded bristle bundle encircled with an O-ring and received in the cup portion of a cupshaped holder having a plastic cup portion.

FIG. 6 is a transverse section taken on the line 6--6 of FIG. 5.

FIG. 7 is a partially exploded view of the brush shown in FIG. 5.

FIG. 8 is an elevational partially sectioned view of a further embodiment of the present invention comprising two annular hub elements of a wheel-type rotary brush according to my invention which is formed of a plurality of such annular hub elements which are plastic and assembled end to end in axial interlocking alignment. Each of the elements includes an annular plastic holder and a plurality of corrugated metal-banded bristle bundles encircled with O-rings and mounted in radial apertures in the holder.

FIG. 9 is a transverse section taken on the line 9-9 of FIG. 8.

FIG. 10 is a transverse section taken on the line l0 10 of FIG. 9.

DESCRIPTION OF PREFERRED EMBODIMENTS Referring now more particularly to the drawing, and especially FIGS. I to 4 inclusive thereof, the embodiment of the invention there illustrated comprises an end brush 1 having a metal holder 2 in the form of a cup portion 3 with an axially extending stem or spindle portion 4 adapted to be received and gripped by the chuck of an appropriate power tool. A bristle cartridge 5 comprised of a bundle of crimped wire bristle material 6 tightly compacted at one end by a rigid corrugated metal band 7 is mounted in the cup portion 3, retained there by an adhesive such as epoxy resin cement, and extends outwardly therefrom to provide a brush face 8 which is generally circular but which has six substantially regularly spaced pointed portions 9 extending beyond the circular main body 10 of the bundle (represented by a broken line in FIG. 3) so that the bristle face 8 has a starlike configuration. The points 9 of the brush face 8 are evenly distributed about the periphery of the brush face in a generally circular configuration and contain a relatively low concentration of bristles by comparison to the circular main bristle body 10. This uniquely shaped brush face 8 results from the unique shape of the binder ring 7.

The bristle cartridge 5 (also referred to as the bristle module" 5) is formed by placing one end of a precut bundle 6 of crimped wire bristles in a seven-sixteenths inch length of 20 gage copper tubing (wall thickness 0.035 inch) having an outer diameter of nine-sixteenths inch. The tubing is then simultaneously crimped inwardly at six regularly spaced intervals (as with a six jaw chuck) to form corrugations of substantially equal width and depth so that the binder ring 7 has a cross section resembling a spur gear having an outer diameter of about one-half inch, a circular pitch taken at the outer diameter of the gear of about 11/12 inch, and a total tooth depth of about one-sixteenth inch. The lands 11 between the gear teeth 12 are relatively wide so that the gear teeth 12 themselves have an average outer width of about three thirtyseconds. Accordingly, the average inner width of each gear tooth 12 is about one thirty-second inch so that relatively few bristles locate in the tooth portions 12 of the binder ring 7. The bristle bundle 6 tends to assume the shape of the binder ring 7 which accounts for the points on the generally circular brush face 8. (It should be noted that any references to gears or the like herein are made for convenience of notation and without regard to whether the object described could actually function as a gear.)

A second embodiment of the present invention is shown in FIGS. 5 to 7 employing a bristle module similar to that shown in FIGS. 1 to 4, that embodiment comprising a rotary end brush 13 having a holder 14 with a polymeric or plastic cup portion 15 molded on a disclike anchor portion 16 at one end of an axially extending stem 17 or spindle. The anchor portion 16 is provided with bosses 18 to prevent the plastic cup 15 from rotating independently of the stem 17. A bristle module 19 comprised of a bundle 20 of crimped wire bristle material bound at one end by a corrugated band 21 of metal is retained at that end in the cup portion 15 by an adhesive 27 such as epoxy resin cement. The bristle module 19 is essentially identical to the module 5 described in FIGS. 1 to 4, having a cross section resembling a six tooth spur gear. The plastic cup 15 portion has two splines 26 on its cylindrical inner surface 22 which project into the spaces between the gear teet 23 keying in the adhesive 27 to prevent the bristle module 19 from turning in the cup 15.

A toroidal rubber collar 23, preferably an O-ring, encircles the bristles 20 where they emerge from the binder ring 21. The O-ring collar 23 is located inside the cup so that the cup 15 reinforces the O-ring 23 against unwanted expansion. This collar 23 serves to protect the bristles 20 and plastic cup 15 from one another and to prevent sharp flexing of the bristles 20 under centrifugal force during brush rotation. The lip of the cup 15 has a slight counterbore to accommodate the O- ring 23, and that lip is swaged inwardly to hold the O-ring 23 in place,

The toroidal rubber collar 23 should be of an elastomeric material, preferably a copolymer of butadiene and acrylonitrile preferably with a hardness of about 70 Shore A durometer, but between about 50 and 90 Shore A durometer. The surface 24 of the collar 23 which engages the bristles during brush operation should be smooth with a convex curvature having a sectional diameter on the order of no less than about one thirty-second inch (a radius of curvature of no less than about one sixty-fourth inch) and preferably about one-eighth inch.

The cup portion 15 of the holder 14 is of a polymeric material, consisting essentially of a solid synthetic resin such as nylon, polypropylene or high impact styrene.

The invention has, thus far, been described with reference to V1 inch (outer diameter) bristle modules for use in it inch end brushes. It is, however, not limited to modules of this size and similar bristle modules within this invention can be constructed for use in end brushes of three-fourths inch and l inch (inner cup diameter) or larger. In each instance, the pitch will be relatively constant (as low as one-tenth 7r inch and preferably about 1r/12 inch at the outer diameter) so that the number of teeth increase as the brush diameter increases. Nine teeth are preferred in the 34-inch brush and twelve teeth are preferred in the 1 inch brush, whereas the total tooth depth remains relatively constant (about one-sixteenth inch), as does the gage of the band material and tooth thickness so that those portions of the brush face which lie outside the circular main bristle body are regularly spaced in a circular configuration and do not contain very many bristles, nor do they protrude very far beyond the circular main bristle body. It will be readily apparent to persons of ordinary skill in the art that in the 3 inch and 1 inch brushes, the pitch of the gearlike binder ring may be lengthened (and the number of teeth reduced) as the bundle size increases without departing substantially from a generally circular brush face. Nevertheless, this will generally be undesirable because it is likely to result in a looser binding which can only be avoided by increasing the tooth depth, thereby increasing the distance beyond the circular main bristle body by which the portions outside such body project. This is seen to be even less desirable in view of the fact that the larger bundles are necessarily less tightly packed because of the reduction in the ratio of the cross-sectional area of the uncrimped ring to the crimped ring as ring diameter increases. Thus, while it is apparent that there is little to be gained by increasing the pitch of the gearlike binder, it may be helpful to decrease the pitch as larger bristle modules are constructed, especially where bristle modules are desired having diameters larger than conventional end brush diameters (about k-l inch) in order to bind the bristles with sufficient tightness to hold them securely in the ring.

Neither is the present invention limited in its application solely to end brushes, since the bristle modules heretofore described are suitable for use in other rotary brushes such as relatively narrow face wheel brushes of the type generally used for cleaning, polishing and deburring operations, or even larger rotary brushing tools of relatively great axial extent for use in sweeping, scrubbing, polishing, cleaning or other treatment of large flat surfaces such as floors or roadways.

Thus, a further embodiment of the present invention is illustrated in FIGS. 8 to 10 comprising a power-driven rotary sweeping brush 30 formed from a plurality of similar or identical relatively narrow annular brush elements 31 assembled end to end in coaxial interlocking relation and adapted for mounting on a drive shaft 32.

A plurality of bristle modules 33 in accordance with the present invention are mounted in generally cylindrical cavities 34 spaced about the periphery of a one piece annular holder 35. The bristle modules 33 are substantially the same or similar to those discussed in connection with FIGS. 1 to 4, and 5 to 7 above, being comprised of a bundle of bristle material 36 tightly bound at one end by a corrugated band of metal 37 having a cross section resembling a spur gear with a circular pitch (at the outer diameter) of about 1r/l2 inch and a total tooth depth of about one-sixteenth inch. In the sweeper brush shown, tampico fibers are employed as are generally preferred, although wire and other brush material may be used or will be preferred in other similar brushes for different purposes, as will be apparent to persons of ordinary skill in the art. The bristle modules 33 are fixed in the hub cavities 34 with epoxy resin or some other suitable adhesive.

The holder 35 is generally annular and has a hub portion 38 and a holder portion 39 located abaxially from the hub portion 38. Cylindrical bristle module receiving cavities 34 are located in the radially outer face 40 of the holder portion 39. The hub portion 38 has a central shaft receiving opening 41 to accommodate the drive shaft 32.

One end of the hub portion 38 is shaped to complement its axially opposed end so that one such brush element 31 interlocks coaxially with the correspondingly opposed side of a like brush element 31. In this manner, a brush of relatively great axial extent (and having a very broad cylindrical brush face) may be built up from a plurality of relatively narrow brush elements 31. The holder 35 is formed of a suitable polymeric material, preferably a solid synthetic resin such as nylon, polypropylene or high impact styrene.

An O-ring 42 or other toroidal collar is preferably employed as described hereinabove and in my copending U.S. Pat. application Ser. No. 763,238, to encircle the bristles 36 where they emerge from the corrugated binder 37. The O-ring 42 is located within the bristle module cavity 34 of the holder portion 39 so that the relatively rigid holder 35 reinforces the O- ring 42 against expansion of its outer diameter. In this manner, the plastic holder 35 and the bristles 36 are protected from one another and the bristles 36 are protected against sharp flexing during operation. Protection of the holder from the bristles is increasingly important as more abrasive brush fill material is employed, as with crimped wire bristles.

The sweeping brush 30 illustrated in FIGS. 8 to 10 of the above is representative of a number of similarly constructed brushes within the present invention embodying modifications adapting the brushes to various particular purposes. In some cases, the bristle modules may be angled to the axis of the drive shaft so that a side-to-side sweeping efl'ect results when the brush rotates. In other cases, the bristle modules may be grouped closely together throughout the brush to form a continuous composite brush face, or small groups of bristle modules may be grouped in a variety of ways to form various tufted brush face configurations. Furthermore, a wheel brush may be formed with a single annular holder having one or more rows of bristle modules, all as will be apparent to persons of ordinary skill in the art.

The binder rings of the bristle modules of the present invention are preferably formed of copper oralumin um or other material having a high thermal conductivity such as in excess of 100 B.t.u. per hour per square foot per degree F. per foot, and preferably in excess of 200 B.t.u. per hour per square foot per degree F. per foot. This conductive band acts as a heat sink tending to draw heat away from portions of the bristles closer to the brush face. During brushing operations, the bristles tend to be hotter towards the brush face and cooler away from the brush face. This tendency, however, does not result in a regular reduction in temperature along the entire bristle length, since the exposed portions of the bristles are cooled by air during rotation and the enclosed portions of the bristles tend to cool relatively slowly. The temperature profile of the bristles at any given time is further complicated by the intermittent nature of brushing operations where, for example, a brush might be alternately driven under power at no load for 5 seconds and then placed under load for 10 seconds intermittently over a period of perhaps 10 minutes. Under these conditions, the enclosed portions of the bristles can build up temperatures which, after the brush has rotated for 5 seconds under no load, may actually be higher than the temperature of the exposed portions of the bristles. It is believed that the segment of the enclosed bristle portion which attains the highest temperatures is that segment which is slightly inside the rim of the holder. And while the average temperature of the enclosed portion of the bristle may stay within acceptable limits, the temperature of that particular segment at the rim of the holder may reach temperatures which are deleterious to the bristles, the plastic cup, and/or the O-ring. Accordingly, by employing a highly conductive metal binder on the bristle module, 1 can conduct heat away from the rim area and lower the bristle temperature at the rim of the holder. Inasmuch as this is an exceptionally high wear area in such brushes, this lowered temperature is believed to have a beneficial effect on brush life.

The bristle module of the present invention is suitable for all types of brush fill material including tampico fiber, plastic coated wire, and plastic monofilaments like nylon fiber. It is also suited for forming bristle modules from straight wire which, in the past, has usually necessarily been knotted around an anchor ring. In addition, the exposed bristles may be encapsulated in polyurethane or the like. See Han: et al. US. Pat. No. 3,142,081.

The bristle module of the present invention and brushes formed therewith lend themselves to efficient and low-cost production methods. For example, in the construction ofprior art end brushes in which the bristles are mounted in solder in the holder cup, it is necessary to first cut a bundle of bristles to size at a first station, whereupon the bundle is bound with a temporary binding and transported to a second station. At the second station, the binding is removed and the bristles are tightly compressed at one end and inserted into the cup. Lastly, the brush face is ground or trimmed smooth.

Construction of brushes according to the present invention commences by first forming a bundle of bristle material; inserting one end of the bundle into a cylindrical metal band; deforming the band inwardly at regularly spaced intervals to form corrugations of substantially identical width and depth and thereby tightly compact the bristle material at that end; and mounting the banded end of the bristle bundle in the holder portion of the rotary brush, preferably with adhesive such as epoxy or the like. The bristles may be aligned with their ends in registry prior to binding so that when bound in the manner of the present invention they provide a relatively fiat brush face requiring little or no finish grinding.

Brushes formed according to the present invention thus may be manufactured in fewer steps by eliminating the need to apply and remove a temporary binding since the metal binder forms a pennanent part of the brush. Neither is it necessary to subsequently compact the bristles since this is accomplished in the binding step. Furthermore, the need for extensive finish grinding is eliminated, handling is greatly simplified, and various other advantages accrue as will be apparent to persons of ordinary skill in the art.

Having thus described my invention, 1 claim:

I. A power-driven industrial rotary end brush comprising a cup-shaped holder; 1

a bundle of brush bristle material; and

a rigid corrugated cylindrical metal band enclosing and tightly compacting one end of said bristle bundle, the corrugations in said band being substantially identical and comprised of alternating ridges and grooves extending generally parallel to the longitudinal axis of said bristle bundle, the other end of said bristle bundle extending from said corrugated band to provide a composite generally circular brush face, said banded bristle bundle mounted with its banded end secured in said holder.

2. A rotary end brush as recited in claim 1 wherein said corrugated metal band has an outer diameter of about one-half inch or greater.

3. A rotary end brush as recited in claim 1 further comprising a collar encircling said bundle of bristle material where it emerges from said band, said collar having a smooth convexly curved bristle support surface for supporting said bristles when they flare radially during brush rotation, said collar being of an elastomeric material with a hardness in excess of about 50 Shore A durometer, and means for reinforcing said collar against substantial expansion during use of said brushin power machinery.

4. A rotary end brush as recited in claim 3 wherein said elastomeric material has a hardness between about 50 and Shore A durometer.

5. A rotary end brush as recited in claim 3 wherein said collar is an O-ring.

6. A rotary end brush as recited in claim 3 wherein the radius of curvature of said bristle support surface is not less than one thirty-second inch.

7. A rotary end brush as recited in claim 3 wherein said collar is an O-ring constructed of elastomeric material having a hardness between about 50 and 90 Shore A durometer.

8. An improved rotary brush as recited in claim 7 wherein the major ingredient of said elastomeric material is a copolymer of butadiene and acrylonitrile.

9. A rotary end brush as recited in claim 3 wherein the material from which the cup portion of said holder is constructed consists essentially of a polymer.

10. A rotary end brush as recited in claim 3 wherein the material from which the cup portion of said holder is constructed consists essentially of a solid synthetic resin.

11. A rotary end brush as recited in claim 3 wherein the material from which the cup portion of said holder is constructed consists essentially of a solid synthetic resin selected from the group consisting of nylon, polypropylene and high impact styrene.

12. A rotary end brush as recited in claim 9 wherein said collar is an O-ring.

13. A rotary end brush as recited in claim 12 wherein the basic ingredient of said elastomeric material is a copolymer of butadiene and acrylonitrile having a hardness between about 50 and 90 Shore A durometer.

14. A rotary end brush as recited in claim 13 wherein said polymer is selected from the group consisting of nylon, polypropylene and high impact styrene.

15. A power-driven industrial rotary brush comprising a circular holder;

a bundle of brush bristle material; and

a rigid corrugated cylindrical metal band enclosing and tightly compacting one end of said bristle bundle, the corrugations in said band being substantially identical and comprised of alternating ridges and grooves extending generally parallel to the longitudinal axis of said bristle bundles, the other end of said bristle bundle extending from said corrugated band to provide a composite generally circular brush face, said banded bristle bundle mounted with its banded end secured in said holder.

16. A rotary brush as recited in claim 15 wherein the material from which said holder is constructed consists essentially of a polymer.

17. A rotary brush as recited in claim 15 wherein the material from which said holder is constructed consists essentially of a solid synthetic resin.

18. A rotary brush as recited in claim 17 wherein said resin is selected from the group consisting of nylon, polypropylene and high impact styrene.

19. A rotary brush as recited in claim 15 further comprising a collar encircling said bundle of bristle material where it emerges from said band, said collar having a smooth convexly curved bristle support surface for supporting said bristles when they bend outwardly during brush use, said collar being of an elastomeric material with a hardness in excess of about 50 Shore A durometer, and means for reinforcing said collar against substantial expansion during use of said brush in power machinery.

20. A rotary brush as recited in claim 19 wherein said collar is an O-ring.

21. A rotary brush as recited in claim 20 wherein the O-ring has a sectional diameter of not less than about one-sixteenth inch.

22. A rotary brush as recited in claim 21 wherein the material from which said holder is constructed consists essentially of a polymer.

23. A rotary brush as recited in claim 21 wherein the material from which said holder is constructed consists essentially of a solid synthetic resin.

24. A rotary brush as recited in claim 23 wherein said resin is selected from the group consisting of nylon, polypropylene and hrghrmpactstyrene

Claims

1. A power-driven industrial rotary end brush comprising a cup-shaped holder; a bundle of brush bristle material; and a rigid corrugated cylindrical metal band enclosing and tightly compacting one end of said bristle bundle, the corrugations in said band being substantially identical and comprised of alternating ridges and grooves extending generally parallel to the longitudinal axis of said bristle bundle, the other end of said bristle bundle extending from said corrugated band to provide a composite generally circular brush face, said banded bristle bundle mounted with its banded end secured in said holder.

3. A rotary end brush as recited in claim 1 further comprising a collar encircling said bundle of bristle material where it emerges from said band, said collar having a smooth convexly curved bristle support surface for supporting said bristles when they flare radially during brush rotation, said collar being of an elastomeric material with a hardness in excess of about 50 Shore A durometer, and means for reinforcing said collar against substantial expansion during use of said brush in power machinery.

4. A rotary end brush as recited in claim 3 wherein said elastomeric material has a hardness between about 50 and 90 Shore A durometer.

5. A rotary end brush as recited in claim 3 wherein said collar is an O-ring.

12. A rotary end brush as recited in claim 9 wherein said collar is an O-ring.

15. A power-driven industrial rotary brush comprising a circular holder; a bundle of brush bristle material; and a rigid corrugated cylindrical metal band enclosing and tightly compacting one end of said bristle bundle, the corrugations in said band being substantially identical and comprised of alternating ridges and grooves extending generally parallel to the longitudinal axis of said bristle bundles, the other end of said bristle bundle extending from said corrugated band to provide a composite generally circular brush face, said banded bristle bundle mounted with its banded end secured in said holder.

20. A rotary brush as recited in claim 19 wherein said collar is an O-ring.

24. A rotary brush as recited in claim 23 wherein said resin is selected from the group consisting of nylon, polypropylene and high impact styrene.