CA2141528A1 - Broom having improved brush arrangement - Google Patents

Abstract

A main rotary broom for a power sweeper machine is described having arrays of brushes disposed at angles relative to a central longitudinal axis of the broom wherein the angles further diverge from one another. When the broom is rotated in use, the brushes sweep debris upwardly away from the street surface and toward a central region above the mid-section of the broom for subsequent handling and collection. An improved integral plastic brush and process for making the brush component is further disclosed for use with the broom.

Description

-- . 21~1~2~ -AttorneyDocketNo. P-301 (Keystone BROOM E~AVING Ii\~PRO~ED BRI~SH ARRANGE~IENT
3 T~:CHNICAL FIELD
4 This invention relates generally to brooms, particularly, those brooms which are useful in motorized sweeper machines and vehicles, and r~ .IIIUlt~ to brushes for such 6 brooms and processes for making these brushes.
7 BAC~GROUND
PriorArt g Conventlonar sweeper machinery exists to remove debris from outdoor roadways o and the interiors of buildings, such equipment ranging in size from large, self-propelled vehicles operated by a seated d~iver to walk-behind power brooms designed to reach 12 more limited work spaces. Machines of either type often utilize a variety of rotating 13 brooms having brushes that impel debris from the work surface elsewhere for remote collection. In designing such brooms, those skilled in the art have generally not addressed controlling the direction where de'oris are thro~vn due, at least in part, to the 6 unavailability of suitable broom ,uluuv~ a that might afford U~UUI ~Ul~ s for uuual~ U~,~i~ practical equipment that achieve this objective. The failure of those in the 8 art to appreciate the problems resulting from this lack of debris control has led to 19 ulll~ a~y wear on other ~;ullll~ull~,llb of the sweeper machinery, as well as suboptimal u~,.ru~lllau1~; in the field, as shall be further elucidated below.
Rev. ino/ss 2i4i~28 PA~A
AttorneyDocketNo. P~301 (Keystone Currently, motorized sweepers employ a horizontally-oriented main broom 2 rotatable about an axis parallel to the plane of the swept surface, the broom consisting of 3 a core typically having a cylindrical shape with fixed bristles that project outwardly to 4 contact that surface. The pattern of dirt removal largely depends on how these bnsties s are oriented when the broom rotates, causing them to contact the surface and impel 6 debris upwardly into the collection system of the vehicle. Large street sweeper vehicles 7 of the type used to clean roadways and other large Lilu-uu~ s are availabie from, 8 among others, Schwarze Industries, Inc. of Huntsville, AL who manufacture a vehicle 9 sold umder the name "Murphy 4000" which is said to be capable of traveling at legal o highway speeds. The design of such sweeper machinery situates a fLat conveyor band I l adjacent the main broom which carries debris swept upwardly from the surface by the 12 broom thence away from the broom toward a col~ection receptacle. This conveyor is 13 driven by opposed belts which are placed under di~u.~,l.u. Liulldt~ tension if the debris is 14 unevenly dispersed on the conveyor band, causing the drive " lrf l~A 11;~111 to e~perience 15 prematurewearovertimefurtherleadingtoe.Ypensive~ "~lebeingperformedon 16 the moving parts of the structure. Similarly, the receptacle wherein the debns is carried 17 can become filled toward one side rather than centrally, vhich exerts greater inertia on a 18 cu~ ull~iillg side of the vehicle's fumctional drive " ,~ ,. " ;~" . for example, the axles 19 and brakes, as well as associated structural members of the vehicle frame including the 20 receptacle itself. This is because the vaned array of bristles extending horizontally along 21 the lengtn of conventional rotary brooms tends to impel debris to one lateral side of the 22 vehicle for collection in a receptacle. This, in turn, biases the load toward one laterai Rev. 1/20195 2 ` 21~1528 PAIENT
Attorney Docket No. P-301 (Keystone) side of the machinery, both as it is deposited upon ehe conveyor belt and carried toward 2 its collection, and then as it rests stored within the receptacle. Therein lies a problem, 3 due to the disproportionate ~vear ~ d by the load-bearing structures of the 4 equipment, for example, belts, pulleys, and bearings ofthe collection m~h~ni~m which s wear out more rapidly on one side of the vehicle than the other, like~vise, the self-6 propelling parts of the vehicle itself, such as the brakes and axles, which must be 7 replaced on one side more frequently than the other.

8 Bristles on these brooms can be assembled together into multiple brushes or as g tufts which are attached directly to the core in a variety of broom ~ullaLIu~.LiO~IS.
o However, these prior rotary dnver discs with cylindrical cores or drums employ fle.Yible I l bristles commonly formed of ~ ;c material that wears away causing the bnstles, 12 to be frequently replaced in a manner which presents still further prob~ems. Namely, the 13 bristles are normally formed into brush assemblies with metallic or heterogeneous irlserts 14 in the brush substrate often using ~lues~ cements and the like. Such materials are incompatible with recycling of the used worn bnstles, making such ass~mblies more 6 eYpensive to replace and requiring inefficient operabons that left much to be desired.
Moreover, ~,ollY~,.ILi~ dl brooms or brushes for industrial and household uses were, likewise, not recyclable because the bristles were generally ~ u~ Lly affixed to the 19 substrate and had to be entirely discarded Therefore, a need exists to provide an improved broom for rotary powered 21 sweepers, which can directbonally control the sweeping of debris within the sweeper.

~ev. 1120/95 3 ~ 21~152~
PA~ENT
Attomey Docke~ No. P-301 (Keysione) A further need exists to provide an improved lcpl~,~blc brush for such brooms.
2 Still further, a need exists to provide such an improved brush with stiff, flexible 3 bristles which are compatible with a struchural backing strip, in terms of fabricating the 4 brush, using the brush in a broom, recycling the brush or any or all of the above.
SUMMA~Y 01;- THE Il~TYENTIOI~
6 According to the invention, there is provided an improved sweeper broom which 7 includes an elongated core which is rotatable about an aYis, with opposed l~n~ih~-lin~
8 ends and a body e~tending bet~veen these ends. Juxtaposed arrays of brushes include 9 bristles that project outwardly from the core and are adapted to contact a given surface lo and oriented with respect to the axis so as to sweep debris off that surface away from the I l respective ends thence toward a selected deposition region adjacent an ~ rl ~ r portion of the body as the broom is rotated about the axis 13 In a preferred ell.bo~ of the invention, the brushes form at least a pair of discrete arrays which are disposed at selected angles relative to the axis, the angles further being divergent from one another.
In another preferred r" ,l~o~ of the invention, the bnstle and substrate of 17 each brush have a distinctive unita~y conshuction, further being directly replaceable as an 18 assembly to the core of the broom.
19 In a further preferred clllbo.lilll~ of the invention, the brushes are fle,Yible and each is arrayed at an angle which presents a helical coil.
Rev. I/20195 4 . . ~ ' ' ' .

~ 21~1~2~
PATENT
Attomey Docket No. P-301 (Keystone An advantage of the invention is the controlled sweeping of debris toward any 2 selected zone of the vehicle for collection in a desired location, resulting in even 3 distribution of the load carried by the moving parts and as located within the storage 4 container of the equipment.
Another advantage of the everl distribution of debris by the present invention is 6 that less wear is ~ by the equipment, reducing the service time and 7 I C~Jla~ li parts of such vehicles as incorporate the instant broom.
8 A further advantage of the present invention is a broom having a replaceable g unitary brush which is simple to Ill~lu~dcLul~ from either primary or secondary o ill~,llw~laatil, materials which are entirely recyclable and flexible to allow easy assembly to a core of the broom by an end user.
12 A still further advarltage of the present invention is a urlitary brush construction 13 capable of a variety of adaptations for sweeping use.

Is B~IEFDESCPIPTION OF THE D~ VGS
6 The invention may be better ~ uhl~cd by reference to the attached Dr~w~n~,s, 17 which illustrate one or more preferred ~mho~iim~nt~ wherein:
13 FIG. I represents a conventional mairl broom for a powered sweeper, with L,-,~lc straight brushes;
~v. 1120195 5 PATENT
Attorncy Docket No P-301 (Keystone FIG. 2 is a perspective Yiew, partially-exploded, of a broom according to the present invention, showing an array of the preferred fiexible replaceable brushes 3 ~ t "~ rd for use with the invention;
4 FIG. 3 is a partial perspective view of a broom of the invention, taken at the s region denoted A, showing a preferred array of the brushes;
6 FIG. 4 is a partial perspective view of a broom of the present invention, similarlv 7 taken at the region denoted A, showing another preferred array of the brushes;
B FIG. S is an end view of a molding apparatus preferably used to fabricate the g preferred unitary brushes of the present invention, sho~ving a representative brush being lo fabricated;
I l F~G. 6 is a sequential view of the molding operation shown in FIG. 5, depicting a mo~ding apparatus having optional cllrl71~menf~l filling means, along with altemative structural support members being molded in the brush;
4 Fm 7 is a sequential view of the molding operation sho~i n in FIGS. 5-6, depicting a finished strip of brush pnor to its removal from the mold;
6 FIG. 8 is an exploded perspective view of a molding apparatus similar to that sho~vn in FIG. S, depicting the use of i"~ .1 reinforcing bristle loops and monofilaments in fabricating brushes according to the present invention;
19 FIG. 9 is a sequential view of tbe molding operation shown in FIG. 8, prior to fusion of the plastic bristles to fomm the unitary brush of the present invention;
Rev I/20195 6 .. . , ~ .

21~1~28 PAIl~NT
AttonneyDoci~etNo. P-301 ~Ceystone FIG. 10 is an end view of a molding apparatus somewhat modified from that of 2 FIG. 1, depicting an altemative unitary brush being fabricated;
3 FIG. 11 is a sequential view of FIG. 10, showing the bristles being softened to 4 fill the mold durirlg the process of tbe invention;
s FIG. 12 is a sequential view o~ FIG. 11, sho~ving a finished unitary brush, prior 6 to removal ~rom the mold, usable as a manual whisk broom;
7 FIG. 13 is a perspective view of one fomm of a unitary brush, constructed in 8 accordance with a preferred aspect of the present invention, usable either as a tuft g component as shown, or adaptable for use as a manual broom;
FIG. 14 is a partial perspective view of a preferred unitary brush strip, I l cvllaLlu~lcd m accordance with the present invention, shown in combination with a tightly-wound helical channel of the preferred broom core, in the region of the boom core 13 denoted B in FIG. 2; and , FIG. 15 is an enlarged perspective view of FIG. 14, showing a ~ tl.11 CacllLdLi VC
array of brushes, individually comprising unitary brushes of the invention, slid into ~,ul-cal~vlldiugchannelsoftheregionBofthecoreinFIG2~
7 Further objects amd advantages may be dl~,vlcc~-~Led by reading the following Derailed Description wherein reference nurnerals are used to denote corresponding fcatures in the Drawin~s :
~ev. 1120/gS 7 214~ ~2~

Attorney Doclcet No. P-30i (Keystone) DETAILED DESCRIPTION
2 Referring now to the Drawings, p~u ~ioul~uly, Fig. 1 shows a broom, generally indicated 3 at l, of the type used as main brooms of street sweeper vehicles which is ~ ldLiv~
4 of those brooms sold, for example, by Keystone Plastics Corp. of So. Plainfield, NJ
s under the name "All-Pro". Broom l futther includes a power driven btush drum 2 which 6 has btistle sttips 3 separably mounted to the drum which, in turn, has ~ilLUlllr~l~llLidlly-7 spaced longitudirlal slots 4 provided for this putpose. A sttip 3 is slidab~y insetted in g each slot into the irltetior of drum 2 and releasably locked in their drum mounted g positions by a coupling bar (not shown) or other suitable substrate that is capable of being disposed matingly and Inn~ihl~ir~liy with the drum. The peripheral ~Ula~ .lL
l l of the slot3 4 to teceive strip 3 on dtum 2 is shown not to be curved but decidedly linear, 12 i. e., extending Inn~itll iin~11y between the ends of the core at an angle of only l-2 degrees relative to the central a,Yis of the core. This linear cl~nhi~ur~finn is due to the limitations of ptior art brushes made of metal which must be preformed to allow for curvature. The present brushes as will be descnbed herein, however, the present invento~
6 has found it possible to allow for disposition of such replaceable brush strips along a 17 curved helical path around the drum. Such a helically-curved configuration is separately 18 disclosed by the present inventor in her co-pending Application Serial No. O /~_, 19 [Ahotney Docket No, 1, along with a preferred plastic strip ~Ol~l u~ L A
20 copy of this previously-filed patent application is submihted ~,ou~ullt llLly with the present Rev. 1120195 8 ` 2141~28 PATENT
Attorney Docket No. P-301 (ICeystorle) application and the entire disclosure thereof expressly incorporated herein by refe}ence 2 and relied upon.
3 Tuming now to FIG. 2, which illustrates a preferred ~mt~o~im~nt of the 4 invention, an improved sweeper broom is generally shown at 10 in a partial state of assemb~y. The broom 10 includes an elongated core, generally indicated at 12, ~vith a 6 wall 14 which is preferably of a metal tube construction having a cylindrical shape and 7 rotatable about a central longitudinal axls denoted by the dotted line labeled (.~). The 8 core 12 has opposed Innritl~rlin~ ends 16, 18 and a body, formed of the wall 14, 9 extending along the axis ~x) between and iL~ ,Ul~ g these ends. Brush strips, o generally indicated at 20, are each formed with rows of bristles 22 preferably comprising I l Ll~ u~ aLic monnfil~lmf~ntc emanating from a base 24. The bnstles 22 on the brush 12 strips 20 proiect radially outwardly from the core 12 and are adapted to contact and 13 sweep a given surface littered with debris because of their flexibility, stiffness and high 14 abrasion resistance. Tbe brushes 20 are assembled to thG core 12 by sliding them into channels 26 from either end 16, 18 of the core 12. The channels 26 are preferably made 16 of metal then bent and twisted so as to be formed with a helical shape, but the channels could altGmatively be of another material such as a plastic, in either case, the channels are adapted to be woumd around and ~ ly affixed to the core 12, for example, by 19 welds, screw fasteners, rivets or the like. The channels 26 preferably have a V-shaped cross-section cnmr~mt nt~y to that of the brush strip 20, extending from either end 16, 21 18 toward a mid-region A of the body of core 12, defining separate patterns of channels 22 with each pattem being wound in an opposing direction from the other. Specifically, the Rev. 1120/95 9 . .

2~4~52~ PATENT
Attorney Doc3 :et No. P-301 (Keystone) pattem of channels denoted by bracket B, opening commonly at end 16, is wound Z Confin~ lcly along an axis (y) angled in one rotational direction with respect to axis (r), 3 while the other pattem of channels, denoted by bracket C and opening commonly at the 4 other end 18, is wound along an axis ~y') which is rotationally opposite to the axis (y) of the first pattem of channels B. When the brush strips 20 are slid into the channels 26 at 6 the respective ends 16, 18 of the core 12, as shown by the dotted assembly lines in FIG.
7 2, there are presented divergent arrays o~brushes 20 corresponding to the pattems A, B
8 of channels which are oppositely, helically wound relative to the central axis (x) and to g one another, respectiYely The brushes 20, thus arrayed, function to sweep debris offthe lo littered surface away from the respective ends 16,18 and toward a selected deposition l l region, indicated by the bracketed segment 26 on either lateral side of the mid-point A, 12 upwardly around the body of the core 12, as the broom 10 is rotated about the axis (~).
13 As discussed above conceming the preferred embodiment of the invention, shown in Fig. 2, the brushes 20 fomn at least a pair of discrete arrays after the pattems of channels B, C which are disposed at selected angles (y ), (y') relative to the central axis 16 (r), the angles (y), (y') further being divergent from one another so as to s~veep debns 17 upwardly from the littered street surface and toward a deposition region ideally located in theupperspacearound;,it..",f~ portionAofbroomlO. It-Yillbeappreciatedthat 19 existing brooms with linear brushes extending between the opposed ends of a core ~E IG.
zo 1) tend to throw dirt and other debris toward one of the ends, which is further interfered 21 with by the pattem of debris swept up from the surface by those vertically oriented rotary Rev. lf2olss lo 2141~ 2 ~ PATENl;
AttorneyDocketNo. P-301 (Keyslone) guKer brooms typically used in ~. ",.l);, Ir1;lll~ with the main brooms of present street 2 sweeper vehicles.
3 Further preferred uuu~. u ,~iulls of the broom 10 of the present invention are 4 shown in FIG. 3, wherein the brushes 26 are arrayed in a reverse-l~"ill~bu.l~
l nnfiPllr~tion, preferably with their respective proximal ends in contact with one another 6 as shown. In FIG. 4 the brushes are shown altematively arrayed in a chevron paKem.
7 Thus, it will be appreciated that the brush strips 20 may have proximal ends which are 8 either spaced Inn~itll~ins~lly from one another (FIG 3) or overlapping (~IG. 4), as long as 9 the paKems of channels A, B, and thus the UUIIC:~UUlldillg arrays of brushes 20 are o helically orientated relative to the axis (~) of the broom 10 and to one another along aYes ~y), (y') as described above, thereby resulting in the divergent arrays brushes 20 furlctioning .où~ c~ ,'y to sweep debris in the manner ~,. .,.i r~ . .i herein by the invention.
14 It will be appreciated that the unique function of the broom 10 could be imparted 15 by structural paKems of brushes which are provided in various ways other than those 16 r. ~ r",l,l,.lr~l by the preferred modu!ar designs using lculi~ce~le fle,Yible strip brushes elsewhere mentioned herein. For example, the strips could comprise brushes prefommed 1~3 with a helical shape which are fastened to a core (not shown) in divergent helical paKems 19 similar to the paKerns A, B described in FIGS. 2-~. Such a non-modular design alluded in the immediately preceding discussion, despite providing divergent arrays of brushes 21 for controlling the direction wherein debris are swept by the broom, would be far less Rev I/20/95 .

21~1528 P~TENT
Attorney Docket No. ~-301 (Keystone) practical for the majority of uses than the modular assembly of the invention.
2 N~ c~ , both the preferred modular construction, and the other approach postulated 3 above, are within the broad scope of function ç~ r~ rd by the present invention.
4 Therefore, the broom 10 as shown in FIGS. 2-4 is preferably a modular assembly, employing separate brushes 20 which comprise flexible strips made of, for example, a 6 molded polyolefin material, which are e.Ytruded into shapes allowing them to be slid into 7 channels 26 provided along core 12, the brush strips 20 having a cross-sectional shape 8 and size to ~ " ~ that of the channels. The channels 26 themselves are integral 9 with the core, e. g, welded or otherwise affLxed in a permanent manner. When a strip 20 lo becomes wom-out, it is simply slid out and removed from its respective retaining channel then replaced with a new strip. An alternative construction, albeit a less practical 2 variation in some respects, utilizes brushes which are formed integra~ly with the core (not 13 shown) into the kinds of arrays which are as taught by the present invention, as alluded to above but, in contrast, these are generally less favorable. For uses which do not require a broom having plastic bristles or which otherwise result in much longer wear possible for the bristles, such that it is feasible to recondition the broom other than by replacing the 17 brushes, as described above, a broom having a core with unitary brushes may be provided Persons skilled in the art will readily appreciate how such an integrally-formed 9 broom could be fabricated by reading tne abo~e description, for example, in a core with metal bristles and backing for use in a scoring operation in highway paving Rev. 1/20/95 12 . ~ -, PA~lT
Attorney Dock~t No. P-301 (Keystone) Given the fore$oing discussion of the use of the preferred brushes in an assembly 2 of the present broom 10, a preferred method of making the brush 20 of the instant 3 invention will now be described. As depicted in FIGS. 5-8, one or more preferred 4 methodsof~,u.~Llu~ thebrush20forusewiththebrooml0,~ .,1r.,.l~lU~dbythe foregoing, comprises the step of providing an elongated open-faced mold, generally 6 indicated at 28, of the desired geometr,v, such as a C-shape uu~ I ~syulld;llg to that of the 7 channels 26 and, in turn, UUllt:~jUUllllillg to the cross-sectional area of base 24 and length 8 of the brush strip 20 (FI&. 2), which mold 28 is heated by an energy source 30 (FIG. 5) g to a ~ llu~ U~r sufficient to so3~en the material intended for use in the mold, in this case o a ~ l ;r. polyolefin such as polypropylene. A row of bnstles 22 made of thepla3tic are positioned within an open throat 32 of the mold 28 with the lower apices of the bristles contacting a heated interior surface of the mold, as shown in FIG. 5. A
downward pressure is applied, as indicated by the large arrow 34, to urge the lower 4 apices of the bristles ag~unst the heated contacting surface of the mold, causing the ends to soften until they deform and the melted plastic 36 flows from the bristles 22 and fills 6 the elongated cavit,v of the mold (FIG. 6). In addition to the plasticized bristle matenal 7 36 flowing in the interstices bet~veen the bristles 22, forming a pool of plastic uullraAuull~lul~ to the base, molten plashc from a ~ u~ source 37 can be injected 19 into the mold, as shown by arrows 38. The mold 28 can be cooled and the finished plastic brush strip 20 solidified (FIG. 7) then removed.
21 As shown in FIGS. 5-7, the brush strip 20 is ~l~ uu~ly formed of a 22 II~n~ihlriinal stack of coinciding corltiguous bristle elements 22 each of which con3ists of Rev. 112~195 13 _ , ~ 2141~2~
PATENT
Attomey Docke~ No. P-3ol (Keystone a length of Lllc~ u~l~.ic m~nofi1~ml~m~-nt, such as poly~ y~ e or nylon. The bristles 2 could either represent discrete mnnnfilAm~nte having a generally round cross-section or 3 could be made of a fLat stock roll of plastic sheet (not shown~ either entirely or partially 4 slit Llalla~ a~ly at intervals ~;OllCau~ illg to the individual bristles, with the unslit 5 border, if any, being subjected to the active heating steps of the molding operation.

6 ~hose skilled in the art will appreciate that the fabncation method disclosed herein does 7 not rely upon the use of glues, cements or other additional fasteners to fabricate the 8 brushes of the invention. The successive bristle members 22 in the brush 20 (FIGS. 5-7) 9 are integrally forrned by mutually fusing successive bridging ends of, for example, the lo monofilaments which project into the heated mold 28. The fusion may be effected in any I l known manner by raising the LCILIU~ LIU1C of the stacked lower apices of the 12 mnnofi1~m~ntc to at least the th.-rmoF1~cti~ polymeric resin fusion t~ Lulc in any 13 known manner such as for example, by applying outside heat from source 30 or by laser 14 beam or the like. The fabncation method herein does not rely upon the use of glues, 15 cements or other additional fasteners to fabricate the brushes of the invention The 6 successive bristle members in the brush are integrally formed by mutually fusing 17 successive bridging ends of, for e.Yample, the monr fii~m~ntc (FIG. 5.) which project into 18 the heated mold..
19 As shown in ~IGS. 8-9, alternatively, individual bnstle elements, generally 20 shown at 40, may be folded at a mid-point to form a generally arrow-shaped head 12 21 having a bottom head and upper lateral legs 44 which extend upwardly. A generally U
22 shaped form may also be used for the bristles, (not shown). The alternative bristle forms ~ev. 1/20/95 14 .

2141~2~
PATENT
Attomey Docket No. P-301 (Xeystone) mentioned above can be especially used when l~ u~ cous bristle elements, e. g., 2 bristles made of metal, are particularly desired to be int~r~r~rsed between plastic 3 mnn~-fil~m~ntc In this regard, metallic bristles, generally shown at 40 in FIG. 8, could 4 have either a flat or round cross-section and be fabricated of any specified dimensions to s result in the desired stiffness and wear properties. It will be ~IJ,ulr,ci~ed that, for a given 6 use, it may be desirable to provide t~tose properties afforded by metallic bristles 40, such 7 as where the broom is used to "score" pavement during road construction or, simply, to 8 add a measure of structural rigidity and wear resistance to a given brush where desired.
g The bottoms of the stacked conti~ouous heads 42 of the metallic bristles 40 are m~rh~ni~lllly interlocked to form the base 24 of an integral strip assembly 20 when the Il apicesofthose;IIlrl~l~ se;lmonofilamentplasticbristles22aremeltedinthemold28 12 according to the process described herein Similar to the steps shown in FIG. 6, 13 additional molten plastic could be flowed into the mold 28 through the throat 32 from the 14 ~,.l,l,1~ ,.. ,1A1 source 37 of supply as the bristles 22 are softening, in order to speed the 15 molding process or intermix another, melt-compatible plastic material for desired 6 structural properties. Similarly, the loop-shaped bristles ~0 made of different materials, 17 maybe;,.~ 1alongtherowofplasticsubstratebristles,1endingaddedstrengthor 18 other enhanced wear properties for a given use. In FIGS. 6 and 8 there is shown still 19 another variation in ~,ullaLlu~,-iu~ the brush strip 20, namely, laying a reinforcing element, 20 which could take the form of a flat steel wire 46 (shown in phantom in FIG. 6), of the 21 same type as used for the h.,~ u~lleuu~ bristles described above in FIGS. 8-9, 22 lengthwise along t~te interior of the mold cavity, then melting the plastic material of the Rev. 1120195 15 ` - 2~41528 AttorneyDocketNo. P-301 (Keystone) ~:
mr~nr~ ment bristles 22 to for~n the base 24, either by pressing the lower apices of the 2 softened bristles 22 into the heated interior surface of the mold 22, additionally supplying 3 molten plastic, such as from source 37 into the mold 28 to fill-in between the apices of ,~
4 the bristles, or a combination of these approaches, to fabricate a brush strip 20 having a ~, base 24 reinforced longitudinally with the steel member 46. The steel bristles 40, formed ..
6 as hairpin-shaped elements alternating between adjacent plastic bristles 22, as shown in 7 FIG. 9, are mrrh:~nio~llly interlocked with the plastic monofilament bristles when the 8 same are melted according to the process disclosed for making the brush 20 of the 9 present invention o As shown by FIGS. l~lI, the afore-mentioned method of making the brush ~
I l strips could readily be adapted to fabncate tufted structures, of the type detailed in FIG.
12 13 wherein the bristles 22 have common apices molded into the shape of a locking tang 13 structure 48 for insertion into a core or other substrate element of a broom. Instead, by modifying the shape and construction of the mold, as ~vill be ~Jlu,;alcd by those skilled 5 irl the art, the tufted structure could take the form of the manual ~vhisk broom molded in 6 FIG. 12. Of course, the structure shown in FIG. 13 could further be fashioned into manual "whisk" brooms for household or other small-scale uses, rather than the assemblies presently required for powered sweeper brooms, by providing an d~J~JI Ul~l idlC
19 snap-in cormection to a handle (not shown). This represents a further improvement to 20 typical consumer brooms having brushes which are largely discarded when overly worn.
21 In contrast, the present invention allows a used brush or an entire broom, in the case of 22 the above-mentioned manual utility broom made of a brush with plastic bristles, to be Rev. I/20/95 16 ~~

PAll~NT
At~orney Docket No. P-301 (Key~tonc) completely recycled and a new l~;yla~ brush a3sembled to the broom rather than 2 scrapping the whole assembly.
3 FIGS 14-15 show the preferred modular assembly of the broom 1~ of the 4 invention, wherein the bristles 22 and base 24 of each brush 20 have the distinctive 5 preferred umitary ~.~JIla~l u~ , the brushes further being lcyla~,L~bl~ as an assembly into 6 one of the patterns B of helically-woumd channels 26 formed adjacent end 16 of core 12, 7 presenting (one of) the l~ a~ e Lollc a~ulldill~ ly diverging arrays of brushes 2o of 8 the broom. A preferred means of assembling the channels 26 is shown, in the form of g screw-type fasteners 50.
o While there have been described and illustrated preferred embodiments of the present invention, it is apparent that numerous omissions and additions may be made tho~ ep rhnef~m~hespmt~hercoe Rev. 1/20195 17 -

Claims (22)

1. An improved sweeper broom comprising:
an elongated core rotatable about an axis and having opposed longitudinal ends and a body extending between these ends; and juxtaposed arrays of brushes including bristles projecting outwardly from the core and adapted to contact a given surface and oriented with respect to the axis so as to sweep debris off that surface away from the respective ends thence toward a selected deposition region adjacent an intermediate portion of the body as the broom is rotated about the axis.

2. The broom of Claim 1 wherein the brushes further comprise flexible strips.

3. The broom of Claim 1 wherein the arrays of brushes are wound helically about the core in opposite rotational directions.

4. The broom of Claim 1 wherein each of the brushes has a proximal end located toward the intermediate portion of the core and a distal end toward a respective end of the core, such that proximal ends of adjacent brushes are essentially coterminous to form a chevron pattern.

5. The broom of Claim 1 wherein each of the brushes has a proximal end located toward the intermediate portion of the core and a distal end toward a respective end of the core, such that proximal ends of adjacent brushes are spaced from one another along the axis of the core.

6. The broom of Claim 1 wherein each of the brushes has a proximal end located toward the intermediate portion of the core and a distal end toward a respective end of the core, such that the proximal ends of adjacent brushes are circumferentially offset from one another to form a herringbone pattern.

7. The broom of Claim 1 wherein the core has channels and the brushes comprise modular strips which slide removably within the channels.

8. The broom of Claim 1 wherein the brushes further comprise flexible polymeric strips adapted to be helically wound about the core in a relatively steep curvature.

9. The broom of Claim 9 wherein the strip further comprises bristles molded in-situ to form a structural backing holding the bristles rigidly perpendicular to the backing.

10. The broom of Claim 1 wherein the brushes further comprise bristles molded of a similar polymeric material as a base of the strip.

11. The broom of Claim 1 wherein the brushes further comprise bristles and a base join the bristles together, the bristle and base being of dissimilar materials.

12. The broom of Claim 1 wherein the brushes further comprise heterogeneous bristles which are of a material different from a base holding them together.

13. The broom of Claim 1 wherein the brushes further comprise heterogeneous bristles held together by a base, individual ones of the bristles being of different materials from one another.

14. The broom of claim 13 wherein some of the bristles are metallic and some of a polymeric material.

15. An improved brush comprising: a plurality of thermoplastic bristles having free ends adapted to contact and sweep a surface and opposing fixed ends fused together into a common base, forming a unitary brush.

16. The brush of Claim 15 wherein the base thereof is fusion bonded into a strip or tuft without the assemblage of additional structural holding members, glues, cements or the like.

17. The brush of Claim 15 wherein the brush comprises a strip further including a reinforcing member extending longitudinally within the base.

18. The brush of Claim 15 further comprising fastening means formed integrally in the base for affixing the strip to a desired substrate or other modular assembly.

19. A method of forming a brush of the type having a base and thermoplastic bristles projecting from the base, the method comprising the steps of:
(a) providing a mold with a throat defining a cavity having a complementary shape to that of the base;
(b) situating a common end of a plurality of the bristles within the throat; and (c) softening the end of the bristles sufficiently to cause the material of the bristles to deform and flow within the mold cavity, filling the cavity and forming the base with upstanding bristles projecting from the base.
.

20. The method of Claim 19 further comprising the step of placing a rigid member within the mold to provide added structural support to the base.

21. The method of Claim 20 further comprising the step of providing an elongated mold with a strip consisting of a material which is heterogeneous from the thermoplastic bristles.

22. A powered rotary sweeper broom comprising:
an elongated cylindrical core rotatable about an axis with opposed longitudinal ends and an intermediate body portion located between those ends;
a first plurality of channels, wound helically around the core and affixed thereto at a selected first angle with respect to the central axis, extending between one of the ends and the intermediate portion of the core;
a second plurality of channels, wound helically around the core and affixed thereto at a selected second angle which is divergent from the first angle, extending between the other end and the intermediate portion of the core, the first and second plurality of channels defining juxtaposed patterns wherein each of the channels is individually adapted to slidably receive an elongated shape complementary to that oft he channel;
a first plurality of elongated replaceable brush strips, each having a base with a cross-sectional shape corresponding to that of the individual channels and a row of upstanding bristles projecting from the base and adapted to contact a surface, which strips are slidably inserted within the first plurality of channels presenting a first array of brushes; and a second plurality of elongated replaceable brush strips, each having a structure like that of the first plurality of brushes, which second plurality of strips are slidably inserted within the second plurality channels presenting a second array of brushes, wherein the first and second arrays of brushes and cooperate to sweep debris upwardly from the surface toward a selected deposition region adjacent the intermediate portion of the body of the core as the broom is rotated about the axis.