US2979749A - Rotary brush - Google Patents

Description

April 18, 1961 BENYAK 2,979,749

ROTARY BRUSH Filed July 11, 1958 INVENTOR. JOHN B. BENYAK 0M0 ofmM ATTORNEYS United States PatetitO ROTARY BRUSH John B. Benyalr, Parma, Ohio, assignor to The Osborn Manufacturing Company, Cleveland, Ohio, a corporation of Ohio .7

Filed July 11, 1958, Ser. No. 748,032

4 Claims. (Cl. 15-179) This invention relates as indicated to a novel rotary brush, and more particularly to a special form of power driven rotary brushing tool in which tufts of brushing material are mounted and arranged to afiord a relatively narrow but dense brush face.

Reference may be had to my prior co-pending Patent No. 2,844,835, for Tufted Brush Construction, of which this application is a continuation-in-part. In such prior application, I disclose a form of tufted power driven rotary brush in which the tufts are flattened and arranged to produce a relatively narrow and dense brush face circumferentially of the tool. This brush is very advantageous for certain purposes where it is desired to brush narrow slots and grooves, but there is nevertheless a tendency for individual bristles to be caught and bent laterally of the brush where they may mar adjoining surfaces and eventually break off. The brushing of such regions as piston ring slots in automotive engine pistons requires not only that the brushing tool have a relatively narrow brush face with the action of the brush material under complete control, but also that such brush face be laterally flexible to accommodate slightly diagonal engagement of the tool into the angles of such slots, etc. Where the slots are exceptionally deep, it is also important that the brushing tool be of narrow crosssection even in regions spaced substantially radially inwardly from the brush face itself.

' In view of the foregoing, it is a principal object of my invention to provide a novel rotary brushing tool which will have a very narrow brush face adapted to'enter slots and the like in work-pieces and in which the brush material'will be under complete control while nevertheless preserving a substantial degree of lateral flexibility;

Another-object is toprovide such rotary brush capable of automatic or semiautomatic manufacture to produce a ,well-balanced tool having brush material uniformly distributed circumferentially thereof.

1 A further, object is to provide such rotary tool which may be of very narrow cross section throughout and not merely at the brush face.

Other objects of the invention will appear as the description proceeds.

To the accomplishment of the foregoing and related ends, said invention then comprises the features hereinafter'fully described and particularly pointed out in the claims, the following description and the annexed drawiir'g 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 principle of the invention may be employed.

"f'ln; said annexed drawing: l'is a semi diagrammatic view showing a plurality Fig. 3 is a transverse cross-section on an enlarged scale taken on the line 33 on Fig. 2;

Fig. 4 is an axial end view of one form of my new rotary brushing tool partly broken away to disclose the internal construction thereof;

Fig. 5 is an enlarged transverse cross-section taken on the line 5-5 on Fig. 4;

Fig. 6 is a fragmentary axial view of a rotary tool constituting a preferred embodiment of my invention;- and Fig. 7 is a transverse cross-section taken on the line 7-7 on Fig. 6.

Fig. l of the drawing shows in a semi-diagrammatic manner threerotary brushes 1, 2 and 3 in accordance with my invention mounted upon an arbor 4 and properly spaced apart by interposed tubular spacers to engage may be mounted on a brush arbor or mandrel.

against all wear and'abrasion at this point.

within corresponding grooves 5, 6 and 7 of an automotive engine piston 8. Such piston will be rotated on its longitudinal axis for complete circumferential coverage of such slots by the brushing tools and the piston may also be reciprocated slightly during engagement with such tools to ensure complete uniform brushing of the grooves.

As shown in Figs. 2-5 inclusive, the brushing tool of this invention may comprise a central steel disc 9 adapted to serve as a hub and having a central aperture 10 which A num ber of small apertures 11 are circumferentially disposed closely within the outer periphery of disc 9, their edges being bevelled or rounded. Through each of such apertures is inserted a tubular sleeve 12, ordinarily of metal, having brush bristle material 13 extending therethrough and protruding therefrom in the form of individual tufts. Such bundles of bristles substantially fill the tubes 12 which are rebent after insertion through aper-l tures 1-1 so that the two tufts protruding from the respective'ends of each tube extend generally radially outwardly from the disc-shaped hub 9. The outer ends 14 of the tubes may be crimped or compressed together both to assist in securing the bristle material therewithin and also to form the tufts into relatively thin flat fan-shaped form. When arranged as illustrated, such tufts obviously afiord a relatively dense but very narrow brush face in substantially the same plane as that of disc 9.

The individual bristles will ordinarily be relatively straight (althoughthey may be slightly crimped on occasion if desired) and will also ordinarily be fairly long in their extent from the ends of tubes 12 to the outer cir cumferential working face of the brush. The bristles are protected where they pass through the disc, being in ef-' fect enclosed within a hinge member guarding them For this reason, together with the provision of elastomeric enclosing and supporting material utilized therewith as ex-' plained below, it is feasible to employ relatively hard brush bristle material, even including steel wire havng a Knoop hardness of 600 or more without danger of an excessive amount of long fracture in use- Such brushes naturally have a much enhanced cutting action. 7 v

- 'Elastomeric material 15 may be molded to enclose the brush material 13 and also such tubular holders 12 as shown in Figs. 4 and 5 of the drawing. When thus molding the elastomeric material such as sponge Neoprene,

of my new brushing tools mounted upon an arbor and spaced simultaneously to engage corresponding piston ring slots "in an automobile engine piston;

f Fig. :2 ha fragmentary axial view of a rotary brush element adapted to be utilized in accordance with m invention-"to "produce my improved brushing tool;

thin flatout'eicircumferential portion 16 0f. the composite tool 'inay'be" flexed laterally'in use as may befiquired',"

Patented Apr. 18, 1961.

a 3 and the outer end portions of the brush bristles may also bend circumferentially of the tool to the extent resiliently yieldingly permitted by the elastomeric material.

A preferred embodiment of my invention is shown in Figs. '6 and'7 of the drawing, affording a brushing .tool of particularly thin cross-section. In such embodiment, a central sheet metal disc 17 is employed having a central aperture 18 adapted for mounting upon an appropriate mandrel or brush arbor. Instead of providing a plurality of tuft securing apertures 11 adjacent the outer periphery of the disc, however, I provide notches having arcuate portions 19 of more than 180 at their inner ends and straight-sided slotted portions 20 extending therefrom to the outer periphery of disc 17. Then, instead of providing double tufts of brush bristle material protruding from the respective ends of the U-shaped sleeve members 12, I employ single tufts 21 of brush material, the inner ends of the tufts being held in retaining tubes 22. The outer ends of such tubes are crimped or flattened and flared as at 23 to form the tufts into thin fan form. The opposite ends 24 of the tubular holders 22 are likewise flared, although ordinarily to a less degree, in order that such flared ends 24 may act as locking means when the tubes 22 are fitted in slots 20 with such flared inner end portions spreading flatwise within the wider arcuate inner portions 19 of the radially disposed notches. Adhesives and like bonding means may be provided within the tubes 22 to assist in retaining the bristles. Such tubes and the bristles themselves are, however, further secured against displacement by molding an appropriate elastomer 25 such as sponge Neoprene to enclose the entire assembly (although the radially inner portion of disc 17 may remain exposed if desired). Since but a single fan-shaped tuft emerges from each tubular holder 22 (in contrast to the Fig. 3 embodiment), the elastomeric material may be intruded between the bristles, and the whole compressed to form an extremely thin laterally flexible, radially outer portion 26 as shown in Fig. 7. Furthermore, inas much as the tubes 22 lie generally in the plane of disc 17 and need not be of appreciably greater thickness than such disc, the entire tool may be of much more narrow cross-section (in contrast to the Fig. embodiment) and is accordingly adapted to be inserted into narrow slots and the like not previously adapted to power brushing.

It will thus be seen that I have achieved the several objectives of my invention by providing a high speed power driven rotary brushing tool having an exceptionally narrow brush face adapted to be inserted into quite deep slots and the like. Such thin layer of brush material is supported for more effective engagement with'the work While at the same time reducing danger of damage to the brush material itself. The brushing tool is so thin in cross-section that it is laterally flexible to a substantial degree despite the employment of elastomeric material intruded therewithin and bonded thereto. The metal parts of the brush assembly may desirably be provided with a thin coating of an epoxy resin composition effective better to bond the elastomeric material thereto. Of'course;

a wide variety of such elastomeric materials may be utilized depending upon the particular operation Where the 7 tool is to be employed.

In the Figs. 4 and 5 embodiment of the invention it will be apparent that the tubular Ushape holders 12 may be capable of a small amount of pivotal or swiveling movement in apertures 11 even when the elastomeric .material has been molded thereover, particularly when but a thin layer of the elastomer is employed. In the Figs. 6 and 7 embodiment, however, the tubular holders 22 are rigidly held against movement relative to the disc in a circumferential direction although a small amount oflatoral-movement may be afiorded. The elastomeric material not-only assists in supporting the brush bristles but also 4 elastomeric material likewise assists in resiliently maintaining the tubular brush material holders properly oriented and protects both the work and the hub partsfrom damage resulting from accidental contact in use.

A wide variety of brush material may be employed, including low damping capacity steel wire having a Knoop hardness of 600 or more, glass filaments, nylon coated wire filaments, tampico fiber and fabric buff material.

The elastomeric material should ordinarly be able to withstand reasonably high operating temperatures without softening or smearing the work. Examples include: Rubber (if operating temperatures are not too high) Neoprene (polychloroprene) Hycar (modified copolymers of butadiene and acrylonitrile) Nylon (polyamide resins) Vinyl plastics (vinyl polymers and copolymers) Melamine resins (melamine-formaldehyde reaction products) It is often advantageous to utilize a thin coating of an appropriate adhesive such as epoxy resin composition adhesives to assist in bonding the elastomeric material to the brush material, particularly wire. Abrasives such as alum'num oxide and silicon carbide may be incorporated in the elastomeric material and also certain filler materials such as bentonite and whiting to render the elastomeric material somewhat more readily erodable at the brushing face of the tool so that such elastomeric material may erode back in use at a greater rate than the brush bristle material, with the result that the latter will protrude sl ghtly therefrom at all times eventhough the elastomeric material may initially extend to the brush face prior to use. An example of a suitable elastomeric composition for employment as the resilient body'is as follows:

When heated in an appropriately, formed mold with the brush assembly, such elastomeric material composition is softened and intruded between the bristles under the action of the blowing agent, and upon further heating and curing a resiliently flex'ble and deformable sponged elastomeric body is formed. Reference may be had to the co-pending application of Ruben 0. Peterson Serial No. 686,499, filed September 26, 1957, for Composite Brushing Tool for a more detailed description of suitable materials comprising the elastomeric body.

Other modesof applying the principle of the invention may be employed, change being made as regards the details described, provided the features stated in any of the following claims or the equivalent of such be employed.

I therefore particularly point out and distinctly claim as my invention:

1. A rotary brush comprising a disc-shaped hub having a large number of generally radially inwardly extending notches in its outer peripheral edge, such notches being wider in their radially inner end portions than adjacent such edge to afford relatively narrow necks thereto, a brush material retaining tube inserted in each such notch in a radial direction closely fi ng s ch neck and. having their inner -end portions co pr s d and generally in the plane of such disc to provide a dovetail key securing them against radially outward withdrawal from said notches, brush material secured in each said tube and extend'ng outwardly therefrom in a thin layer generally in the plane of said disc to form a thin circular brush face, said tubes being compressed and flared in their outer end portions to spread said brush material into thin fan-shaped layers thus to form such brush face, and elastomeric material intruded between said bristles slightly to space them apart, sad elastomeric material being molded to form with said bristles a thin laterally flexible blade-like outer peripheral portion adapted to be inserted into slots in work-pieces, wherein said elastomeric material extends radially inwardly to enclose said notches and tubes.

2. A rotary brush comprising a disc-shaped hub having a large number of generally radially inwardly extending notches in its outer peripheral edge, such notches being wider in their radially inner end portons than adjacent such edge to aflord relatively narrow necks thereto, a brush material retaining tube inserted in each such notch in a radial direction closely fitting such necks and having their inner end portions compressed and flared generally in the plane of such disc to provide a dovetail key securing them against radially outward withdrawal from said notches, brush material secured in each said tube and extending outwardly therefrom in a thin layer generally in the plane of said disc to form a thin circular brush face, said tubes being compressed and flared in their outer end port'ons to spread said brush material into thin fan-shaped layers thus to form such brush face, and elastomeric material intruded between said bristles slightly to space them apart, said elastomeric material being molded to form with said bristles a thin laterally flexible blade-like outer peripheral portion adapted to be inserted into slots in work-pieces, wherein said elastomeric material extends radially inwardly to enclose said notches and tubes, and said elastomeric material is a sponge Neoprene composition adapted to erode away at the work face in use slightly more rapidly than the brush material wears back.

3. A rotary brush comprising a disc-shaped hub having a large number of generally radially inwardly extending notches in its outer peripheral edge, such notches being wider in their radially inner end portions than adjacent such edge to afford relatively narrow neck:

thereto, a brush material retaining tube inserted in each such notch in a radial drection closely fitting such necks and having their inner end portions compressed and flared generally in the plane of such disc to provide a dovetail key securing them against radially outward withdrawal from said notches, brush material secured in each said tube and extending outwardly therefrom in a thin layer generally in the plane of said disc to form a thin circular brush face, said tubes being compressed and flared in their outer end portions to spread, said brush material into thin fan-shaped layers thus to form such brush face, and elastomeric material intruded between sad bristles slightly to space them apart, said elastomeric material being molded to form with said bristles a thin laterally flexible blade-like outer peripheral portion adapted to be inserted into slots in work-pieces, wherein said brush material is hard steel wire, and said elastomerIc material is a sponge Neoprene composition adapted to erode away at the work face in use slightly more rapidly than said bristles wear back, said elastomeric' material extending substantially from such work face radially inwardly to enclose said notches and tubes.

4. In a rotary brush having a disc-shaped hub adapted to be mounted on an arbor or the like, said hub having a plurality of dovetail notches in its outer peripheral edge, brush elements secured in said notches comprising brush material holders fitting in said notches having flaring inner end portions etfective to resist the eflect of centrifugal force in use, and a single flat tuft of brush material secured in each said holder and lying generally in the plane of said disc, including elastomeric material intruded into said brush material to form therewith a thin peripheral portion of said brush, said elastomeric material extend ng radially inwardly to enclose said notches and holders.

References Cited in the file of this patent UNITED STATES PATENTS 1,475,074 McLaughlin Nov. 20, 1923 2,648,084 Swart Aug. 11, 1953 2,826,776 Peterson Mar. 18, 1958 2,844,835 Benyak July 29, 1958 FOREIGN PATENTS 523,850 Great Britain July 24, 1940 537,303 France May 20, 1922

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