WO2024258958A1

WO2024258958A1 - Apparatus and method for bending brush fibers to provide an angled brush

Info

Publication number: WO2024258958A1
Application number: PCT/US2024/033600
Authority: WO
Inventors: Akira Chanthabandith; Todd M. CLEMONS; David M. Loughney
Original assignee: Ultrafab Inc
Current assignee: Ultrafab Inc
Priority date: 2023-06-12
Filing date: 2024-06-12
Publication date: 2024-12-19
Anticipated expiration: 2025-12-12
Also published as: US20240407542A1

Abstract

An apparatus (10) for bending brush fibers (16) has a rotating shaft (12) with an outer surface (13) along which a flexible backing strip (15) of a brush (14) partially wraps around to dispose fibers (16) extending from the backing strip (15) outwards as such brush (14) travels along the outer surface (13) of the shaft, and an energy delivery head (26), positioned along the backing strip (15) when curving around the shaft (12), bends the fibers (16) as the backing strip (15) travels along the outer surface (13) of the shaft. Energy delivered by the head (26) deforms the fibers (16), when being bent by the head (26), to retain at least a portion (16a) of the fibers bent at an angle (17) with respect to the backing strip (15) to provide an angled brush (14a). The angled brush (14a) has fibers (16) each deformed along a region (17a), at a location between the backing strip (15) and an end or tip (16c) of the fiber, to bend at the angle (17) from the region (17a) to the end or tip of the fiber (16c).

Description

APPARATUS AND METHOD FOR BENDING BRUSH FIBERS TO PROVIDE AN ANGLED BRUSH

This application claims priority to U.S. Provisional Patent Application No. 63/507,721, filed June 12, 2023, which is incorporated herein by reference.

Field of the Invention

The present invention relates to an apparatus and method for bending brush fibers, and particularly to an apparatus and method for bending brush fibers extending from a backing strip in which each of the fibers are bent to extend at an angle with respect to a longitudinal (length) dimension of the backing strip. The invention is useful to reorient brush fibers at an angle from a substantially upright or perpendicular orientation with respect to the backing strip to provide a brush for use in applications benefiting from having a brush with angled fibers, referred to herein as an angled brush. The present invention thus further relates to an angled brush having fibers each deformed bent at an angle with respect to a longitudinal dimension of the backing strip of the brush from which such fibers extend.

Background of the Invention

Vibratory conveyers and bowl feeders are used in manufacture to singulate and orient bulk piece parts. Often surfaces of such conveyor and bowls are lined with brush material, such as manufactured by 3M® Company under the trademark of Brushion® which are brushes with synthetic fibers embedded in a resinous backing. One version thereof, Brushion® 20°, has fibers tilted at an angle with respect to their backing layer, which have been applied to the surface of vibratory conveyors or feeder bowls in order to move parts more quickly, hear less noise in the process, and reduce chance of damage to fragile or polished parts. While useful, 3M® Company discontinued Brushion® products in 2022 requiring alternative sources of angled brush material. Ultrafab, Inc. of Farmington, NY USA, a Roto Group subsidiary, manufactures brushes having a flexible backing and generally upright fibers, such as under the Ultra Nylon® trademark. Thus, it would desirable to bend existing brushes designed without any angular tilt, such as Ultra Nylon® brushes, to have a desired angle orientation as may be useful in applications benefiting from having brushes with angled fibers, such as along vibratory conveyer and bowl feeder surfaces. Summary of the Invention

Accordingly, it is a feature of the present invention to provide an apparatus and method for bending brush fibers extending from a backing strip in which each of the fibers are bent to extend at an angle to provide an angled brush.

It is another feature of the present invention to provide an angled brush having fibers each being deformed bent at an angle with respect to a longitudinal dimension of a backing strip of the brush from which such fibers extend.

Briefly described, the present invention embodies an apparatus having a rotating shaft having a curved circumferential outer surface along which a flexible backing strip of a brush partially wraps around to dispose fibers extending from the backing strip outwards as such brush travels along the outer surface of the shaft, and an energy delivery head positioned along the backing strip when curving around the shaft to bend the fibers as the backing strip travels along the outer surface of the shaft, in which energy delivered by the head deforms the fibers, when being bent by the head, to retain at least a portion of said fibers bent at an angle with respect to a longitudinal dimension or length of the backing strip, wherein such portion for each of the fibers starts at a location between the backing strip and an end or tip of the fiber, and extends to the end or tip of the fiber.

The fibers of the brush preferably extend substantially upright from the backing strip prior to being bent at the angle to form the brush into an angled brush. The brush is delivered to the shaft in a first direction, and after traveling along the shaft of the apparatus exits the shaft in a second direction. In the preferred embodiment, the energy delivery head is part of a horn for delivering ultrasonic energy (i.e., vibrations) through such head. Less preferably, energy delivered by the head is heat energy by a heat generator, such as heating element or hot air blower coupled to the head.

The energy delivery head has a portion configured to bend and delivery energy to heat each of the fibers as the fiber contacts at least such portion of the head when travelling by the head, responsive to rotation of the shaft, to retain the fiber bent at the angle. The energy delivery head has a bottom surface and a front facing the shaft that preferably provides a front edge parallel to the axis of rotation of the shaft and the width of the brush along the backing strip, and at least such front edge of the head bends at an angle the fibers and delivers energy heating the fibers as each pass by contacting at least such front edge part of the head to retain the fiber deformed bent at such angle. Thus, the portion of the head configured to bend and delivery energy to heat each of the fibers by contacting such head includes at least its front edge and optionally other parts of the head extending from the front edge.

The front edge of the energy delivery head is spaced by a gap from the outer surface of the shaft along which the brush travels, and the size of the angle is principally in accordance with the size of the gap, and also by the radial position of the head, along its front edge, about the rotational axis of the shaft. Varying the size of the gap and/or such radial position of the head with respect to the shaft can adjust the apparatus to provide different fiber angle orientations, and also adjusts the starting location of a region along each of the fiber is deformed bent at the angle by energy applied by the head, and hence adjusts the length of the bent portion of each of the fibers to their end or tip. The front of the energy delivery head facing the shaft’s outer surface may have other configurations than a straight edge in accordance with the brush fiber density and fiber profile, such as a curved edge, or a surface with or without curvature, or other portion, so long the head contacts the fibers as they pass or travel by to provide bending them to the desired bent angle. The angle may be at or between 10 and 80 degrees, but preferably between at or between 10 and 30 degrees, such as 20 degrees, with respect to the longitudinal dimension of the backing strip.

The present invention also provides a method for bending brush fibers extending from a backing strip comprising steps of: rotating a shaft having curved circumferential outer surface along which the backing strip of a brush partially wraps around to dispose fibers extending from the backing strip outwards as such brush travels along the outer surface of the shaft, bending the fibers as the backing strip travels along the outer surface of the shaft, and delivering energy to the fibers when bent to retain at least an portion of the fibers bent at an angle with respect to a longitudinal dimension of the backing strip. The bending and delivering energy steps are preferably carried out simultaneously utilizing an energy delivery head, and such energy delivery head operates by ultrasonic energy, and less preferably, by heat energy.

The delivering energy step preferably deforms each of the fibers along a region, at a location between the backing strip and the end or tip of the fiber distal from the backing strip, in which such bent portion of the fiber extends from the region to the end or tip of the fiber. The method may further comprise the step of providing the brush to the shaft while the rotating step is carried out wherein the fibers of the brush, prior to the bending and delivering energy steps, extend at least substantially upright from the backing strip. The method may also comprise the step of removing the brush from the shaft while the rotating step is carried out after the bending and delivering energy steps are carried out.

The present invention further provides an angled brush having a plurality of synthetic fibers, and a backing strip having a surface from which each of the plurality of fibers extends a length to an end or tip of the fiber. Each of the fibers is deformed along a region, at a location between the backing strip and the end or tip of the fiber, to bend at an angle from the region to the end or tip of the fiber. Such angle may be with respect to a longitudinal dimension of the backing strip. The region of the fiber is deformed preferably by application of ultrasonic energy, and less preferably heat energy, to retain the fiber bent when disposed bent at the angle. For example, the angle each of the fibers is bent may be at or between 10 and 80 degrees, such as 20 degrees, with respect to the longitudinal dimension of the backing strip. The angle is the same for each of the fibers of the angled brush. The backing strip of the brush is preferably flexible at least along its longitudinal dimension.

By bending fibers of a brush at a desired angle after the brush’s fabrication to provide an angled brush, the present invention avoids customized fabrication of angled brushes which attach angularly oriented fibers to one surface of a backing strip or base, such as described in U.S. Patent No. 8,376,471 and International Patent Application Publication No. WO/2008/091599. It has been found that angled brushes of the present invention in which their fibers are bent at an angle from their original orientation present in the brush provides sufficiently angled brushes for applications benefiting from having a brush with angled fibers. The apparatus of the present invention also can be readily configured to make from brushes with substantially upright oriented fibers different ones of angled brushes at different angles and/or different lengths of bent portion to the end or tip of the fibers.

Brief Description of the Drawings

The foregoing and other features and advantages of the invention will become more apparent from a reading of the following description in connection with the accompanying drawings in which:

FIGS. 1A, IB, and 1C are perspective, front, and side views, respectively, of the apparatus of the present invention where an energy delivery head for bending fibers of the brush is shown in an up position with respect to an example brush prior to operation of the apparatus; FIG. ID is a cross-sectional view of FIG. 1A along line ID-ID in the direction of arrows at end of the line;

FIG. 2 is the same front view as FIG. IB of the apparatus of the present invention with the energy delivery head moved to a down position for bending brush fibers as they travel responsive to rotation of a shaft to reorient the fibers to bend at an angle to provide an angled brush;

FIG. 3 is a broken enlarged view of FIG. 2 showing the energy delivery head, brush fibers, and shaft in more detail;

FIGS. 4 A and 4B are perspective and side views, respectively, of an example brush of FIGS. 1 A-D, 2 and 3 with generally upright fibers prior to being operated upon by the apparatus of FIGS. 1A, IB, 1C, and 2; and

FIGS. 5 A and 5B are perspective and side views, respectively, of example angled brush after operation of the apparatus of FIGS. 1 A, IB, 1C, and 2 upon the brush of FIGS. 4A and 4B.

Detailed Description of the Invention

Referring to FIGS. 1A, IB, 1C, ID, and 2, an apparatus 10 of the present invention is shown having a motor driven rotating shaft 12 with a curved circumferential outer surface 13. A backing strip (or base) 15 of a brush 14 wraps to curve partially around shaft 12 to dispose fibers 16 extending from backing strip 15 outward as the brush 14 travels along outer surface 13 with rotation of shaft 12. Rotation of shaft 12, denoted by arrow 22, is about a rotational axis 23. The shaft 12 may be of rigid material(s) preferably of metal, such as steel, in which its outer surface 13 is smooth. A channel (not shown) may be provided along outer surface 13 to guide the backing strip 15 as it travels upon shaft 12. FIGS. 1A, IB, 1C, and ID (FIGS. 1A-D) show the brush 14 mounted along shaft 12 prior to operation of apparatus 10.

To rotate shaft 12, shaft 12 is coupled to a rotary motor 18, via a rotary bearing fixture 19 and coupler 18a, as best shown in FIG. ID. The rotary bearing fixture 19 has two bores, one for receiving and mounting end 12a of shaft 12, and the other for receiving and mounting one end 21 of the coupler 18a to motor 18. Rotary bearing fixture 19 represents a housing mounted to a plate 20 having bearings 19a (FIG. 3) and internal features, such as a shaft, coupling rotation motion of coupler 18a to shaft 12. Shaft 12 extends cantilevered horizontally by the rotary bearing fixture 19 over a front portion of plate 20. Apparatus 10 further has an ultrasonic horn 28 having an energy delivery head 26 positionable adjacent shaft 12 as shown in FIGS. 2 and 3 for delivering ultrasonic energy to fibers 16 of brush 14 when moved from an up position 34a (FIGS. 1A-D) to a down position 34b (FIGS. 2 and 3) as denoted by arrows 35. The horn 28 extends to an ultrasonic converter 29 which drives the horn in response to electrical signals as typical of an ultrasonic generator such as used in welding. To move head 26 between up position 34a and down position 34b, a linear motion drive 30 is provided.

If needed to assist in maintaining the shaft’s rotation axis 23 position with respect to head 26 of horn 28, plate 20 and shaft 12 may be extended from that shown in FIGS. 1A-D, and shaft 12 mounted for rotation in two other rotary bearing fixtures (not shown) mounted to plate 20 along the shaft 12 such that backing strip 15 is received there upon between such fixtures. Each such rotary bearing fixture having an interior cylindrical structure mounted to shaft 12 to rotate with shaft 12 upon bearings within a stationary generally cylindrical structure mounted to plate 20. Additionally, such two rotary bearing fixtures may both be mounted, via an additional mounting plate or structure (not shown) to plate 20, in which such additional mounting plate or structure is movable between fixed position with respect to plate 20 using fasteners, slots, slide members, bolts, or other releasable fixing mechanism to plate 20 to assist in moving and aligning shaft 12 to different positions as needed relative to head 26 of horn 28 in setting up apparatus 10 to operate on brush 14.

Linear motion drive 30 has a vertical rotatable shaft 40 (FIG. ID) journaled for rotation in a linear slide frame 41 at the top 41a and bottom 41b thereof. Frame 41 is mounted to vertical portions of a pair of L-shaped brackets 33 which have horizontal portions 32 mounted to plate 20. The shaft 40 extends through an aperture 41c (FIG. ID) along the top 41a of frame 41 for rotation by a rotary (stepper) motor 42, via coupler 42a, through a hole in a bracket 43 upon which motor 42 is mounted. Bracket 43 is mounted to vertical portions of L-shaped brackets 33 via a plate 44. A movable carriage 46 (FIG. ID) is mounted to ultrasonic converter 29 via a linear slide interface plate 48. Shaft 40 is threaded and engages a threaded aperture 47 extending through carriage 46 such that rotation applied to the shaft 40 by motor 42 translates the carriage 46 up or down along shaft 40 while linear bearings along slot(s) 49 extend from carriage 46 ride along vertical rail(s) 50 mounted along frame 41 between top 41 a and bottom 41b thereof. Motors 18 and 42 operate responsive to electrical signals and/or supplied power to provide desired motor operation. Other mechanisms for moving head 26 may be utilized, such as ultrasonic converter 29 being mounted instead to a vertical shaft or piston of a pneumatic cylinder to temporarily fix the head 26 at each of its up and down positions by air flow pumped or released from the pneumatic cylinder. Further, linear motion drive 30 may be similar to that typical of ultrasonic welding equipment having a movable horn. As such, the present invention is not limited to any particular means or mechanism for vertical linear translation of horn 28 and its head 26 with respect to shaft 12.

To operate apparatus 10, linear motion drive 30 is operated by a user via signals to motor 42 to move the head 26 of horn 28 to a down position 34b (FIGS. 2 and 3) from up position 34a (FIGS. 1A-D), motor 18 is activated to rotate shaft 12, and ultrasonic converter 29 is activated to supply ultrasonic energy to horn 28 and its head 26 in order to start bending fibers 16 of brush 14 as they travel through apparatus 10. Responsive to rotation of shaft 12 in the direction of arrow 22, brush 14 is fed from a supply spool or reel (not shown) travelling in a linear direction, denoted by an arrow 24 (longitudinally oriented with backing strip 15), onto shaft’s outer surface 13. While the brush 14 is being rotated along outer surface 13, fibers 16 of brush 14 are bent at a desired angle 17 by head 26 of horn 28 adjacent shaft 12, as will be described below in more detail in connection with FIGS. 2 and 3, and then exits shaft 12 now as an angled brush 14a traveling in the linear direction, denoted by arrow 25 (longitudinally oriented with backing strip 15), to a take-up spool or reel (not shown) which may be rotated by a motor at the same speed as rotation of shaft 12. Arrows 24 and 25 are in opposite directions to each other.

FIGS. 4 A and 4B show an example segment of brush 14 prior to being operated by apparatus 10 in which fibers 16 extend at least substantially upright or straight, perpendicular to the length and width of backing strip 15, when horizontally disposed as shown. FIGS. 5A and 5B show an example segment of angled brush 14a after brush 14 is operated upon by apparatus 10, where each fiber 16 has at least a portion 16a bent at angle 17 to a bent orientation from its original substantially upright (perpendicular) orientation of FIGS. 4A and 4B with respect to a longitudinal or length dimension 51 of backing strip 15, denoted by a dashed line in FIGS. 5A and 5B, when backing strip 15 of brush 14a is horizontally disposed as shown. As shown in FIG. 5A and 5B, fibers 16 each have a substantially upright (perpendicular oriented) portion 16b, with respect to longitudinal dimension 51, as the fiber

16 extends away from the top side or surface 15a of backing strip 15, and then bends at angle

17 along a region 17a of the fiber at a desired location between backing strip 15 and an end or tip 16c of the fiber distal from the backing strip. The particular location of regions 17a along the fibers 16 where its bent orientation starts is adjustable in apparatus 10 so that different lengths of bent portions 16a can be provided from region 17a to the end or tip 16c of fibers 16 for different ones of angled brushesl4a than shown in FIGS. 2, 3, 5A and 5B.

While fibers 16 of brush 14 of FIGS. 4 A and 4B are shown extending perpendicular in an upright or straight orientation to backing strip 15, such fibers are of synthetic material having a degree of flexibility along their length and thus may extend slightly less than perpendicular and hence considered substantially upright when the brush 14 is manufactured with respect to backing strip 15. The angular degree of bend of each fiber 16 may be considered along the complementary angle to angle 17 from fibers 16 upright (perpendicular) orientation.

Optionally, if angled brush 14a of lesser widths are desired, one or more blades (not shown) are longitudinally oriented, perpendicular to the width dimension of backing strip 15, in order to slit angled brush 14a along its backing strip 15 to provide a plurality of angled brushes of desired widths each on to a different take-up spool or reel.

As shown in FIGS. 2 and 3 with energy delivery head 26 of the horn 28 in the down position 34b, head 26 is positioned along backing strip 15 of the brush 14 as it curves traveling along shaft 12 to bend fibers 16 extending from backing strip 15. Ultrasonic energy delivered from head 26 heats fibers 16 of the brush 14 when being bent by head 26 thereby retaining portion 16a of fibers 16 bent at angle 17. Angle 17 of bent fibers 16 is denoted in FIG. 3 with respect to longitudinal dimension 51 of horizontally disposed backing strip 15 after leaving shaft 12 for purposes of illustration, such angle 17 of bent fibers 16 is also present in brush 14a after they contact head 26 along rotating shaft 12. In particular, head 26 has a bottom surface 27a, and a front which faces surface 13 of shaft 12, preferably providing a front edge 27b extending along a dimension parallel to rotational axis 23 of shaft 12 and width of backing strip 15. Front edge 27b is spaced from outer surface 13 of shaft 12 by a gap 36 that at least provides clearance for backing strip 15 along surface 13 as front edge 27b contacts fibers 16 extending from such backing strip 15. With rotation of shaft 12, each of fibers 16 in response to contacting head 26 along front edge 27b, and optionally a portion of head’s bottom surface 27a extending from front edge 27b, bends backward (generally opposite in direction of arrow 22) as the fiber 16 passes by head 26 in the gap 36 with backing strip 15 between head 26 and outer surface 13 of shaft 12, while ultrasonic energy delivered by head 26 to the material of the fiber 16 heats the fiber to retain its bent orientation deformed at angle 17. The location or area along each fiber 16 where the front edge 27b of head 26 contacts the fiber defines bent fiber region 17a where bent portion 16a start along the fiber 16 extending to the end or tip 16c of the fiber. Optionally, a stationary guide member (not shown) may be provided having two opposing side walls through which the fibers 16 pass between as they travel along shaft 12 to assist in orienting any stray (not substantially upright) ones of fibers 16 from the backing strip 15 at or near the ends of its width to contact head 26 when passing thereby in gap 36, as described above. Further, optionally fiber 16 after temporarily contacting front edge 27b while being rotated thereby may touch (or contact) along part of the front of head 26 facing shaft 12 that extends from front edge 27b until past head 26.

To adjust the down position 34b of energy delivery head 26 with respect to shaft 12 to accommodate different ones of brush 14 and/or select a different bent angle 17 of fibers 16, the position where ultrasonic converter 29 is mounted to plate 48 may be adjusted, e.g., by mounting screws and/or bolts to slots along plate 48, and/or mechanical stop/clamp along rail(s) 50 limiting downmost position of carriage 46 along shaft 40, in order that (i) front edge 27b is at a different angular or radial position, than as illustrated at 90 degrees, along the 0 and 180 degrees as labeled in FIG. 3 of an arc 37, of brush backing strip 15 as it follows the curvature of outer surface 13 of shaft 12, and/or (ii) size or distance of gap 36 is adjusted along such arc 37 about a virtual radial line 38 at the angular or radial position of head 26 about the shaft’s rotational axis 23 to front edge 27b of head 26. Thus, in setting up apparatus 10 to operate on brush 14, the horn head’s down position 34b is positionally adjustable as desired to contact fibers 16 as they rotate along shaft 12, but in the preferred embodiment, the down position 34b has bottom surface 27a of head 26 is not greater than 90 degrees radial position along arc 37, and hence is maintained beside shaft 12 either horizontally, or above, the shaft’s rotational axis 23, with desired size of gap 36.

The adjustment of the size of gap 36 and/or the radial position of energy delivery head 26 about shaft’s rotational axis 23 thereby changes the position of head 26 relative to shaft 12 to enable selection of location of region 17a where angle 17 is formed and retained by applied energy of head 26 along each of fibers 16 between backing strip 15 and their end or tip 16c, thereby enabling the length of bent portion 16a of fiber 16 to be selected as desired when brush 14 is processed by apparatus 10. As such, regions 17a may be selected to start closer or farther along fibers 16 with respect to backing strip’s top side or surface 15a than as illustrated in FIGS. 2, 3, 5A, and 5B in angled brush 14a. Thus, region 17a may be closely adjacent backing strip 15 or near the end or tip 16c of fibers 16, or anywhere in between, for fibers 16 of a desired one of angled brush 14a. In the particular example of FIGS. 2, 3, 5A and 5B, bent portions 16a for each of fibers 16 are at or approximately 30% of overall fiber 16 length (i.e., combined lengths of portions 16a and 16b between backing strip 15 to end or tip 16c), but depending on position of region 17a along each of 1'ibers 16 other percentages of bent portion 16a to overall fiber 16 length may be provided for different ones of angled brush 14a depending on the desired length of bent portion 16a.

It was found that optimal bending of fibers 16 occurred while brush 14 travels along arc 37 in order that fibers 16 flair outwards along a virtual radial line 38 when contacting energy delivery head 26. While not shown to scale in FIGS. 2, 3, 5A, and 5B, the angle 17 of fibers 16 of angled brush 14a may be 20 degrees from the horizontal or longitudinal dimension 51, but other angle 17 may be formed by repositioning head 26 to different fixed positions relative to shaft 12, such as at or between 10 and 80 degrees where bent portions 16a of fibers 16 extend in a direction at that angle away from backing strip 15. However preferably, angle 17 is at or between 10 and 30 degrees, such as 20 degrees, in such angled brush 14a applications involving placement along surfaces of vibratory conveyers or bowl feeders. The size of angle 17 of bent fibers 16 is believed principally controlled by the size of gap 36 along virtual radial line 38 to the front edge 27b, where increasing the gap 36 size decreases angle 17 bent by apparatus 10 in angled brush 14a, and vice versa, but also by the radial position of virtual radial line 38 of the head 26, along its front edge 27b, about the rotational axis 23 of shaft 12. The rate of rotation of shaft 12 is set to assure adequate dwell time head 26 contacts each fiber 16. For example, such rate may be 4 foot/minute, but other rate may be used, and may need to be adjusted higher or lower depending on the density of the fibers being more or less, respectively, passing between the head 26 and shaft 12 to assure adequate dwell time of the head 26 upon each of the fibers 16 to retain its bent orientation at angle 17. While the front of head 26 preferably provides a straight edge 27b, as illustrated in the figures parallel to shaft’s rotational axis 23 along a rectangular bottom shaped head 26, the front of the head 26 facing surface 13 of the shaft 12 may have other configurations, such as an edge with curvature, or a surface with or without curvature, or other portion configured to bend fibers 16 passing by head 26, depending on fibers 16 of brush 14, fiber density, or shape of outer profile of the fibers 16 along the cross-sectional width of brush 14, in accordance with the particular application of the angled brush 14a formed from brush 14 by apparatus 10. For example, head 26 may be a downwardly extending cylinder contoured to have two opposing parallel sides which taper downwardly to provide an elongated rectangular flat (or horizontal) bottom surface 27a narrower than shown in the FIGS. 1A-D but similarly positionable parallel to the dimension of shaft’s rotational axis 23 to provide straight edge 27b. Such tapered head 26 is useful being sized to accommodate the abovedescribed optional stationary guide member when present, so that head 26 when in down position 34b is disposed between opposing side walls of such guide along gap 36 to contact all fibers 16 of brush 14 passing thereby.

Horn 28 and ultrasonic converter 29 represents an ultrasonic generator device of a typical ultrasonic welder or generator. Ultrasonic converter 29, while shown schematically as a block, represents typical components of an ultrasonic stack for enabling horn 28 operation. A controller supplies power for operating horn 28 to deliver a desired amount of ultrasonic energy via head 26 of horn 28 by controlling duration and amplitude of ultrasonic energy applied by the horn. A user interface (e.g., buttons, touch screen display, switches, or the like) of a controller as typical of ultrasonic welding equipment, may be provided to operate horn when in down position 34b, as well as to control motors 18 and 42 operation. For example, ultrasonic energy applied may be provided vibrations at 20Khz, but other ultrasonic frequencies may be used. The head 26 mounted or attached to horn 28 is made of a rigid material suitable for transmitting ultrasonic energy, such as titanium.

Backing strip 15 is thin, for e.g., 0.02 to 0.03 inches thick, may be made of nylon, or other synthetic material, such as polypropylene, and is flexible along at least its length or longitudinal dimension so that it can follow the curvature of outer surface 13 of shaft 12 when placed onto shaft 12. Backing strip 15 has a bottom side or surface 15b that can frictionally engage the outer surface 13 of shaft 12 when wrapped partially there around, and top side or surface 15a from which fibers 16 extend. The fibers 16 may be nylon filaments or pile, but other synthetic filament material, such as polypropylene, may be used. Preferably, nylon filaments are woven to fix them in the backing strip material to provide fibers 16 such that they extend at least substantially upright therefrom to a desired height, such 0.5 inches, but fibers 16 may extend to other height, such as at or between 1/8 inch to 1 inch. Groups of fibers 16 each extend in rows substantially across the width of the backing strip 15, where adjacent rows are spaced equally from each other along the length or longitudinal dimension of the backing strip. The spacing of adjacent rows, and spaced between adjacent fibers in each row, provides the desired density of fibers from the brush. Preferably, fibers 16 substantially extend along the entire length and entire width of the backing 15 of brush 14, and preferably in an array of columns and rows, but may otherwise be arranged along backing strip 15. For example, brush 14 may be a brush manufactured by Ultrafab, Inc. of Farmington, NY USA, a Roto Group subsidiary, under die mark Ultra Nylon®, but other brushes with synthetic generally or substantially upright fibers from a flexible backing strip or base may be used which can be mounted for rotation about shaft 12 and operated upon by apparatus 10 to bend their fibers at a desired angle 17.

In the preferred embodiment, energy delivery head 26 is part of horn 28 for delivering ultrasonic energy (i.e., vibrations) through such head from an ultrasonic converter that converts electrical signals into ultrasonic vibrations to the head transmitted via horn 28 to fibers 16. Less preferably, energy delivered by the head is heat energy by a heat generator, such as heating element or hot air blower coupled to the head. This may be achieved by mounting a heat generator for head 26 to linear motion drive 30 instead of ultrasonic converter 29 and horn 28. Heat generator has a heating mechanism of an electrical heating element coupled to head 26, or a hot air blower onto head 26, in which head 26 may be shaped differently than shown in figures in order to accommodate such heating mechanism, while providing the front of head 26, preferably front edge 27b, or other configuration facing surface 13 of shaft 12, to obtain desired angled brush 14a. A thermocouple (temperature) sensor mounted to head may be present to monitor and control application of heat applied to head 26 so that heat energy within a proper temperature range from head can be conveyed to fibers 16 when being bent in the same manner as described earlier to retain bent angle 17.

From the foregoing description, it will be apparent that there has been provided an apparatus and method for bending brush fibers to provide an angled brush, as well as an angled brush which may be made by such apparatus and method. Variations and modifications in the herein described apparatus, method, and angled brush will undoubtedly suggest themselves to those skilled in the art. Accordingly, the foregoing description should be taken as illustrative and not in a limiting sense.

Claims

Claims:

1. An apparatus for bending brush fibers extending from a backing strip comprising: a rotating shaft having a curved circumferential outer surface along which the backing strip of a brush travels to dispose the fibers extending from said backing strip outwards; and an energy delivery head, positioned along said backing strip when traveling along said shaft, bends said fibers in which energy delivered by said energy delivery head deforms said fibers, when being bent by said energy delivery head, to retain at least a portion of said fibers bent at an angle with respect to a longitudinal dimension of the backing strip, wherein said portion for each of said fibers starts at a location between the backing strip and an end or tip of the fiber, and extends to the end or tip of the fiber.

2. The apparatus according to Claim 1 wherein said energy delivery head has a portion configured to bend and delivery energy to heat each of said fibers as the fiber contacts at least said portion of said energy delivery head when traveling by said energy delivery head, responsive to rotation of said shaft, to retain the fiber deformed bent at said angle.

3. The apparatus according to Claim 1 wherein said backing strip wraps at least partially along said curved circumferential outer surface of said shaft while travelling along said shaft.

4. The apparatus according to Claim 1 wherein said energy delivered by said energy delivery head is ultrasonic energy.

5. The apparatus according to Claim 1 wherein said energy delivered by said energy delivery head is heat energy.

6. The apparatus according to Claim 1 wherein said shaft has an axis of rotation, said energy delivery head has a surface with a front edge parallel to said axis of rotation, and at least said front edge of said energy delivery head bends and heats each of said fibers as the fiber passes by said energy delivery head to retain the fiber deformed bent at said angle.

7. The apparatus according to Claim 6 wherein said front edge of said energy delivery head is spaced by a gap from said outer surface of said shaft along which said brush travels, and said angle is at least in accordance with a size of said gap.

8. The apparatus according to Claim 1 wherein said fibers of said brush extend at least substantially upright from said backing strip prior to be bent at said angle to form said brush into an angled brush.

9. The apparatus according to Claim 1 wherein said brush is delivered to said shaft in a first direction and after traveling along said shaft exits said shaft in a second direction.

10. The apparatus according to Claim 1 wherein said energy delivery head is movable between a down position adjacent said shaft to enable bending of fibers and an up position away from said shaft.

11. The apparatus according to Claim 1 wherein said angle is at or between 10 and 80 degrees, with respect to a longitudinal dimension along which the backing strip extends when horizontally disposed, in accordance with one or more of a size of a gap between the outer surface of the rotating shaft and said energy delivery head, and a radial position of said energy delivery head about an axis of rotation of said shaft.

12. The apparatus according to Claim 1 wherein said backing strip is flexible along at least said longitudinal dimension to enable said backing strip to travel along said outer surface of said shaft.

13. A method for bending brush fibers extending from a backing strip comprising steps of: rotating a shaft having a curved circumferential outer surface along which the backing strip of a brush travels to dispose the fibers extending from said backing strip outwards; bending said fibers as said backing strip travels along said outer surface of said shaft; and delivering energy to said fibers when said bending step is being carried out to retain at least a portion of said fibers bent at an angle with respect to a longitudinal dimension of said backing strip.

14. The method according to Claim 13 wherein said energy delivering step deforms each of the fibers along a region, at a location between the backing strip and an end or tip of the fiber distal from the backing strip, in which said portion of the fiber extends from the region to said end or tip of the fiber.

15. The method according to Claim 13 further comprising step of: providing said brush to said shaft while said rotating step is carried out, wherein said fibers of the brush, prior to said the bending and delivering energy steps, extend at least substantially upright from said backing strip.

16. The method according to Claim 13 further comprising step of: removing said brush from said shaft while the rotating step is carried out after said bending and delivering energy steps are carried out.

17. The method according to Claim 13 wherein said bending step and said delivering energy steps are carried out simultaneously utilizing an energy delivery head.

18. The method according to Claim 13 wherein said energy is ultrasonic energy.

19. The method according to Claim 13 wherein said energy is heat energy.

20. A brush comprising: a plurality of synthetic fibers; a backing strip having a surface from which each of said plurality of fibers extends a length to an end or tip of the fiber; and each of said fibers being deformed along a region, at a location between said backing strip and the end or tip of the fiber, to bend at an angle from said region to the end or tip of the fiber, in which said angle is with respect to a longitudinal dimension of said backing strip.

21. The brush according to Claim 20 wherein said region along each of said fibers is deformed by ultrasonic energy to retain the fiber bent when disposed bent at said angle.

22. The brush according to Claim 20 wherein said region along each of said fibers is deformed by heat energy to retain the fiber bent when disposed bent at said angle.

23. The brush according to Claim 20 wherein said angle is at or between 10 and 80 degrees with respect to said longitudinal dimension of the backing strip.

24. The brush according to Claim 20 wherein said angle is 20 degrees with respect to said longitudinal dimension of the backing strip.

25. The brush according to Claim 20 wherein said backing strip is flexible along at least said longitudinal dimension.

26. The brush according to Claim 20 wherein a same one of said angle is provided along each of said fibers.

27. The brush according to Claim 20 wherein said backing strip has a width, and said plurality of fibers extend from said surface grouped in rows of different ones of said fibers that at least substantially extend along said width of said backing strip, and every two different ones of said rows are spaced from each other along said longitudinal dimension of said backing strip.