U.S. patent application number 14/576423 was filed with the patent office on 2015-04-16 for method for manufacturing a flexible strip brush.
The applicant listed for this patent is Felton, Inc.. Invention is credited to Marc Godin, Matthew Gorham, Donald James Marler, Lawrence Nieder, Roy Wirth.
Application Number | 20150101734 14/576423 |
Document ID | / |
Family ID | 43353005 |
Filed Date | 2015-04-16 |
United States Patent
Application |
20150101734 |
Kind Code |
A1 |
Wirth; Roy ; et al. |
April 16, 2015 |
METHOD FOR MANUFACTURING A FLEXIBLE STRIP BRUSH
Abstract
A method for manufacturing a flexible strip brush element is
disclosed. A multiplicity of thermoplastic monofilaments
respectively having first ends and second ends are arranged in
substantially parallel fashion and at a prescribed density. Heat is
applied to the first ends of the monofilaments so as to melt the
first ends of the monofilaments. The monofilaments are transported
toward an extrusion die comprising an outlet. Molten thermoplastic
resin is extruded from an extrusion die outlet, wherein the outlet
is shaped to produce a base having a top and a bottom. The first
ends of the monofilaments are brought into physical contact with
the top of the base as the base emerges from the extrusion die
outlet. The monofilaments and the base are cooled so that the first
ends of the monofilaments are fused to the top of the base and the
second ends of the monofilaments are free.
Inventors: |
Wirth; Roy; (Northfield,
NH) ; Godin; Marc; (Pittsfield, NH) ; Nieder;
Lawrence; (Concord, NH) ; Gorham; Matthew;
(Hampstead, NH) ; Marler; Donald James; (Emmaus,
PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Felton, Inc. |
Londonderry |
NH |
US |
|
|
Family ID: |
43353005 |
Appl. No.: |
14/576423 |
Filed: |
December 19, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12795248 |
Jun 7, 2010 |
|
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14576423 |
|
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61187813 |
Jun 17, 2009 |
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Current U.S.
Class: |
156/72 |
Current CPC
Class: |
B29K 2105/0088 20130101;
B29K 2995/0082 20130101; B65G 51/00 20130101; B29K 2077/00
20130101; B65G 45/18 20130101; B29K 2021/003 20130101; A46B 13/001
20130101; A46B 5/06 20130101; A46B 3/04 20130101; B29C 48/155
20190201; B29L 2031/42 20130101; A46D 3/045 20130101; B29K 2101/12
20130101; B29K 2101/10 20130101 |
Class at
Publication: |
156/72 |
International
Class: |
A46B 3/04 20060101
A46B003/04; B29C 47/02 20060101 B29C047/02 |
Claims
1. A method for manufacturing a flexible strip brush element, the
method comprising the steps of: arranging, in substantially
parallel fashion and at a prescribed density, a multiplicity of
thermoplastic monofilaments respectively having first ends and
second ends; applying heat to the first ends of the monofilaments
so as to melt the first ends of the monofilaments; transporting the
monofilaments toward an extrusion die comprising an outlet;
extruding molten thermoplastic resin from an extrusion die outlet,
wherein the outlet is shaped to produce a base having a top and a
bottom; bringing the first ends of the monofilaments into physical
contact with the top of the base as the base emerges from the
extrusion die outlet; and cooling the monofilaments and the base so
that the first ends of the monofilaments are fused to the top of
the base and the second ends of the monofilaments are free.
2. The method of claim 1, wherein: transporting the monofilaments
toward an extrusion die comprising an outlet is in a first
direction; and extruding molten thermoplastic resin from an
extrusion die outlet is in a second direction.
3. The method of claim 2, wherein the thermoplastic resin used for
the extruded base has a flexural modulus less than 80 ksi as
determined by ASTM D790 when solid, the second direction is
approximately perpendicular to the first direction, and between the
emergence of the base from the extrusion die outlet and the cooling
of the monofilaments and the base, movement of the base is made to
undergo a change of direction from the first direction to the
second direction.
4. A method for manufacturing a flexible strip brush element, the
method comprising the steps of: arranging, in substantially
parallel fashion and at a prescribed density, a multiplicity of
thermoplastic monofilaments respectively having first ends and
second ends; transporting the monofilaments in a first direction
toward an extrusion die comprising an outlet; extruding uncured
thermosetting resin in a second direction from the extrusion die,
wherein the outlet is shaped to produce a base having a top and a
bottom; bringing the first ends of the monofilaments into physical
contact with the top of the base as the base emerges from the
extrusion die outlet; and curing the base so that the first ends of
the monofilaments are fused to the top of the base and the second
ends of the monofilaments are free.
5. The method of claim 4, wherein: transporting the monofilaments
toward an extrusion die comprising an outlet is in a first
direction; and extruding molten thermoplastic resin from an
extrusion die outlet is in a second direction.
6. The method of claim 5, wherein the thermosetting resin used for
the extruded base has a flexural modulus less than 80 ksi as
determined by ASTM D790 when cured, the second direction is
approximately perpendicular to the first direction, and between the
emergence of the base from the extrusion die outlet and the curing
of the base, movement of the base is made to undergo a change of
direction from the first direction to the second direction.
7. A method for manufacturing a flexible strip brush from a
plurality of flexible strip brush elements, the method comprising
the steps of: arranging in side-by-side fashion a plurality of
adjacent flexible strip brush elements, the strip brush elements
each comprising: a base having a top and a bottom; a multiplicity
of monofilaments, each of the monofilaments having a proximal end
and a distal end; and a bristle attachment region, wherein the
monofilaments are arranged in substantially parallel fashion, the
proximal ends of the monofilaments are attached to the top of the
base by way of the bristle attachment region, the distal ends of
the monofilaments are free and collectively form a bristle end
zone, within the bristle attachment region, there is intermingling
of a first material from the base and a second material from the
monofilaments, and within the bristle attachment region, the first
material from the base fills interstices between the monofilaments;
and mutually bonding the adjacent strip brush elements so that the
free distal ends of the monofilaments cooperate to form a common
bristle end zone.
8. The method of claim 7, wherein the base having a top and a
bottom comprises a flexural modulus less than 80 ksi as determined
by ASTM D790.
9. The method for manufacturing a flexible strip brush according to
claim 7, further comprising forming at least one side bonding
region.
10. The method for manufacturing a flexible strip brush according
to claim 7, further comprising forming a bottom bonding region
comprising substantially a width of the base.
11. The method for manufacturing a flexible strip brush according
to claim 9, wherein the side bonding region is formed by one or
more species selected from among the group consisting of
coextrusion, lamination, glue, heat, and solvent.
12. The method for manufacturing a flexible strip brush according
to claim 7, further comprising forming at least one bottom bonding
region.
13. The method for manufacturing a flexible strip brush according
to claim 12, wherein the bottom bonding region is formed by one or
more species selected from among the group consisting of
coextrusion, lamination, glue, heat, and solvent.
14. The method according to claim 12, further comprising pressing a
heated nonstick tool against the bottoms of the bases while
dragging the tool therealong so as to cause melting of the bases to
a depth sufficient to cause the flexible strip brush elements to
become mutually joined when the melted bases are allowed to cool
and resolidify.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional application of copending
U.S. patent application entitled "Flexible Strip Brush, Flexible
Belt Brush, and Method for Manufacturing the Same" having Ser. No.
12/795,248, filed Jun. 7, 2010, and claims priority to U.S.
Provisional patent application entitled "Flexible Strip Brush,
Flexible Belt Brush, and Manufacturing Method Therefor," having
Ser. No. 61/187,813, filed 17 Jun. 2009, both of which are hereby
incorporated by reference herein in their entirety.
FIELD OF THE INVENTION
[0002] The present invention is generally related to brushes, and
more particularly is related to a flexible strip brushes and
flexible belt brushes.
BACKGROUND
[0003] FIGS. 1 through 3 show a stapleset brush 900 in accordance
with the prior art. As can be seen in the perspective view of the
stapleset brush 900 in FIG. 1, brush bristles 905, represented in
FIGS. 1 through 3 as a bundle of individual bristles, extend from
drilled or molded holes 901 in a solid block of material such as
rubber, leather, metal, or wood serving as base 902. As can be seen
from the side sectional view of FIG. 2, the side shown at FIG. 2
being the same side as faces the reader in FIG. 1, brush bristles
905 contain tufts or bundles of strands that are folded over, the
folded portion being held against the surface at the bottom of the
hole 901 by a wire staple 907 or other rigid fastener. This is
shown in the end sectional view of FIG. 3, the end shown at FIG. 3
being, for example, the end at the right in FIG. 1. At FIG. 3, it
is possible to see the profile of the staple 907, this being such
that the ends of the staple 907 are embedded and held firmly within
the bulk material of the base 902.
[0004] Several difficulties arise when one attempts to employ the
stapleset structure 900 of the prior art shown in FIGS. 1 through 3
as a belt brush or in another such application where flexibility is
required.
[0005] For example, a belt brush employed in a conveyor or cleaning
application might be made to undergo flexible deformation as it is
driven within the transport mechanism of which it forms a part. For
example, a belt-driven conveyor brush or cleaning brush in such an
application might be driven by pulleys or made to wrap around
idlers that cause the brush to bend around the radius of curvature
of the pulley or idler. However, where the base 902 is fashioned
from a rigid material such as metal or wood, the stapleset brush
900 will, needless to say, be inflexible and thus unsuitable for
use as a belt brush in such an application.
[0006] Furthermore, even where the base 902 is fashioned from a
less rigid material such as rubber, the fact that the staple 907 is
typically stiffer than the material of the base 902, which is to
say that the staple 907 and the base 902 in such case would have
dissimilar moduli of elasticity, can cause localized stresses to
occur in the vicinity of the staple 907, such stresses being made
all the more severe to the extent that the staple 907, which is
typically fashioned from a cut piece of wire, has sharp ends,
corners, or edges. Such stresses can cause increased wear,
shortened life, and failure of the stapleset brush 900. Of course,
any stresses arising due to presence of the staple 907 will only be
aggravated and made more intense by flexible deformation of the
sort that such a belt brush will typically be made to undergo,
further contributing to increased wear, shortened life, and failure
of the stapleset brush 900.
[0007] Moreover, to properly embed the staple 907 within the base
902, the base 902 must have a certain minimum height, the height
direction here being the direction in which the bristles 905 extend
from the base 902 in FIGS. 1 through 3. However, thickness of the
base 902 in this height direction contributes to the second moment
of inertia about an axis perpendicular to a plane formed by the
face of the base 902 indicated in, for example, FIG. 2.
Specifically, the thickness of the base 902 in the height direction
causes the base 902 to resist bending such as would cause the ends
of the base 902 to flex so as to conform to a radius of curvature
centered on an axis emerging from the plane of the base 902 at a
point above or below the stapleset brush 900 as viewed in FIGS. 1
and 2. Forcing the base 902 of the stapleset brush 900 to conform
to such a radius of curvature despite this stiffness or resistance
to bending due to the large second moment of inertia, as might be
done were the stapleset brush 900 to be employed as a belt brush
driven by pulleys in a transport mechanism, for example, would
create high stresses in the base 902, both in the vicinity of the
staple 907 as well as in the vicinities of the top and bottom of
the base 902. Such stresses can also cause increased wear,
shortened life, and failure of the stapleset brush 900.
[0008] In addition, in a structure in which the bristles 905
contain tufts that are folded over and attached by stapling to the
base 902, there will of necessity be gaps between adjacent tufts
due to presence of the wall containing base material 902 serving as
partition between adjacent holes 901. In the structure shown in
FIGS. 1 through 3, bristle density will be discontinuous along the
length direction (i.e., the direction extending from left to right
in FIG. 1 or FIG. 2), bristle density being high where bunched
bristles 905 emerge from a hole 901, and being low between holes
901 where no bristles 905 emerge. This effect can to some extent be
mitigated by employing a design in which bristles 905 fan out from
their proximal regions, where they emerge from the holes 901, to
their distal regions, where the bristles 905 collectively form a
bristle end zone. Depending on the application in question, this
bristle end zone might serve as conveyor drive face for transport
of small objects including, but not limited to, nuts, bolts, pills,
and/or other such objects to be conveyed, might serve as cleaning
brush for cleaning parts or surfaces, or might serve as sealing
surface for sealing a shuttle canister within a pneumatic tube
transport system for use at a bank drive-up window, for example.
Nonuniformity in bristle density within the bristle end zone can
cause poor conveyor drive characteristics in an application in
which the bristle end zone serves as conveyor drive face, poor
cleaning performance in an application in which the bristle end
zone serves to sweep or scour a floor or other surface, poor
sealing in an application in which the bristle end zone serves as
sealing surface, and other performance problems. In addition, the
gaps that exist between adjacent tufts impose a limit on the
maximum bristle density that can be achieved, and this limit on
maximum achievable bristle density can also adversely impact
achievable bristle end zone characteristics.
[0009] In such a design according to the prior art, there are
practical limits to the width (i.e., the direction extending from
left to right in FIG. 3) of the bristle end zone formed by the
bristles 905 that can be achieved. For example, beyond a certain
width, it may be difficult for the staple 907 to retain the
bristles 905 at all points along the bottom of the hole 901.
Furthermore, as can be seen in FIG. 3, proper embedding of the
staple 907 within the base 902, such as will prevent the cut ends
of the staple 907 from protruding from the sides of the base 902,
necessitates that there be a certain minimum wall thickness to
either side of the hole 901 in the width direction (i.e., the
direction extending from left to right in FIG. 3). This being the
case, even if one were to, for example, laminate multiple flexible
strip brush elements together in side-by-side fashion in an attempt
to extend the effective width of the brush, a stapleset brush 900
having design as shown in FIG. 3 would be limited with respect to
the density of bristles 905 that is achievable in the width
dimension due to presence of this minimum wall thickness to either
side of the hole 901 in the width direction, in similar fashion as
the limitation presented by the thickness of the wall serving as
partition between adjacent holes 901 in the length direction which
was described above.
[0010] The physical properties of the material employed as bristles
905 will in general impose constraints on overall tuft height,
width, and length. For example, if the bristles 905 contain
polypropylene or other such thermoplastic substance or other
material having similar modulus of elasticity, mechanical
properties of the material employed for the bristles 905 will limit
the dimensions of the bristles 905 to certain practical ranges from
the standpoints of manufacturing and performance.
[0011] For example, to achieve a brush 900 having bristles 905 with
the requisite physical characteristics for the application in
question, and in particular to achieve a brush 900 having such
desired physical characteristics at the ends of the bristles 905
forming the bristle end zone, it will in general be necessary to
impose limits on the ranges that can be employed for bristle length
and diameter, and such ranges will be further limited upon
considering the requisite average bristle density (e.g., number of
bristles per square inch) and allowable nonuniformity in that
bristle density.
[0012] For these and other reasons, a stapleset brush 900
manufactured in accordance with the prior art as shown in FIGS. 1
through 3 will often be inadequate except when employed in a
comparatively narrow assortment of limited configurations. For
example, as explained above, the stapleset brush 900 of the prior
art may be inadequate where width is desired at the bristle end
zone formed by the ends of the bristles 905, where high bristle
density is desired at the bristle end zone formed by the ends of
the bristles 905, where good uniformity in bristle density is
desired at the bristle end zone formed by the ends of the bristles
905, or where it is desired that the stapleset brush 900 exhibit
good flexibility with respect to flexure about an axis
perpendicular to the plane of the bristles 905, such as would be
the case were the stapleset brush 900 to be fashioned in an endless
loop for driving by pulleys and idlers.
[0013] Although the difficulties mentioned above by way of example
are described as applying to the stapleset structure 900 of the
prior art shown in FIGS. 1 through 3, one or more of the foregoing
difficulties may apply to structures from the prior art other than
those shown in FIGS. 1 through 3. Furthermore, while various
aspects and embodiments of the present invention may overcome one
or more of the difficulties described above, not every difficulty
mentioned above is necessarily overcome by all aspects and
embodiments of the present invention, and in fact there may be
aspects and embodiments of the present invention that overcome
difficulties in the prior art other than those mentioned by way of
example above.
[0014] Whether such difficulties exist in the prior art shown in
FIGS. 1 through 3 or in other structures from the prior art that
are not shown, a heretofore unaddressed need exists in the industry
to address such deficiencies and inadequacies.
SUMMARY
[0015] Embodiments of the present invention provide, among others,
a method for forming flexible strip brush element. Briefly
described, a multiplicity of thermoplastic monofilaments
respectively having first ends and second ends are arranged in
substantially parallel fashion and at a prescribed density. Heat is
applied to the first ends of the monofilaments so as to melt the
first ends of the monofilaments. The monofilaments are transported
toward an extrusion die comprising an outlet. Molten thermoplastic
resin is extruded from an extrusion die outlet, wherein the outlet
is shaped to produce a base having a top and a bottom. The first
ends of the monofilaments are brought into physical contact with
the top of the base as the base emerges from the extrusion die
outlet. The monofilaments and the base are cooled so that the first
ends of the monofilaments are fused to the top of the base and the
second ends of the monofilaments are free.
[0016] Other embodiments, systems, methods, and features, and
advantages of the present invention will be or become apparent to
one with skill in the art upon examination of the following
drawings and detailed description. It is intended that all such
additional systems, methods, features, and advantages be included
within this description, be within the scope of the present
invention, and be protected by the accompanying claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Many aspects of the invention can be better understood with
reference to the following drawings. The components in the drawings
are not necessarily to scale, emphasis instead being placed upon
clearly illustrating the principles of the present invention.
Moreover, in the drawings, like reference numerals designate
corresponding parts throughout the several views.
[0018] FIG. 1 is a perspective view of a stapleset brush
manufactured in accordance with the prior art.
[0019] FIG. 2 is a side sectional view of the stapleset brush shown
in FIG. 1.
[0020] FIG. 3 is an end sectional view of the stapleset brush shown
in FIGS. 1 and 2.
[0021] FIG. 4 is a drawing showing a method for manufacturing a
flexible strip brush element in a first embodiment in accordance
with a first aspect of the present invention.
[0022] FIG. 5 is an end sectional view of a flexible strip brush
element such as might be manufactured using the manufacturing
method described with reference to FIG. 4.
[0023] FIG. 6 is a perspective view of a flexible belt brush which,
in accordance with a second aspect of the present invention,
contains three flexible strip brush elements similar to the
flexible strip brush element shown in FIG. 5.
[0024] FIG. 7 is a perspective view of a portion of a flexible belt
brush that has been fashioned in the form of an endless loop
through use of a scarf joint to mate the ends of a linear section
of a flexible belt brush similar to that shown in FIG. 6 or FIG.
11.
[0025] FIG. 8 is a bottom view of a portion of a flexible belt
brush that has been fashioned in the form of a jointless spiral by
wrapping a single long flexible strip brush element, such as that
shown in FIG. 5 or FIGS. 9 and 10A, around a cylindrical mandrel in
helical fashion.
[0026] FIG. 9 is a perspective view of a flexible strip brush
element in a second embodiment in accordance with the first aspect
of the present invention.
[0027] FIG. 10A is an end sectional view of the flexible strip
brush element of FIG. 9.
[0028] FIG. 10B is an end sectional view of an embodiment of the
flexible strip brush element of FIG. 9 with ribs on the bottom
side.
[0029] FIG. 11 is an end sectional view of a flexible belt brush
manufactured from three flexible strip brush elements similar to
the flexible strip brush element shown in FIGS. 9 and 10A.
[0030] FIG. 12 is a drawing showing a method for manufacturing a
flexible belt brush similar to that shown in FIG. 11 from two
flexible strip brush elements similar to the flexible strip brush
element shown in FIGS. 9 and 10A.
[0031] FIG. 13 is a drawing showing a flexible belt brush
manufactured in accordance with an embodiment of the present
invention, the flexible belt brush being shown in a configuration
intended to emphasize the superior flexibility thereof with respect
to flexure about an axis perpendicular to the plane of the
bristles.
[0032] FIG. 14 is another drawing showing a flexible belt brush
manufactured in accordance with an embodiment of the present
invention, the flexible belt brush being shown in a configuration
intended to emphasize the superior flexibility thereof with respect
to flexure as well as torsion.
[0033] FIG. 15 is yet another drawing showing a flexible belt brush
manufactured in accordance with an embodiment of the present
invention; the flexible belt brush being shown in a configuration
intended to emphasize the superior flexibility thereof with respect
to flexure as well as torsion.
DETAILED DESCRIPTION
[0034] One aspect of the present invention is a flexible strip
brush element and a manufacturing method therefor FIG. 4
illustrates a method for manufacturing a flexible strip brush
element 150 according to a first embodiment of the present
invention.
[0035] As shown by FIG. 4, a stock of bristle monofilaments 155 of
suitable diameter, e.g., 0.006 inch, preferably 0.003 inch to 0.024
inch, most preferably 0.006 inch to 0.016 inch, separately
manufactured from nylon, polypropylene, or other suitable
thermoplastic resin by extrusion using a multistrand die, for
example, are cut to desired length, preferably 0.20 inch to 6.00
inch, most preferably 1.50 inch to 3.00 inch, and are arranged with
desired density at a location a suitable distance from the outlet
of an extrusion die. As the monofilament stock 155 is transported
toward the extrusion die outlet, heat 105 is applied to one end of
the monofilaments 155 so as to melt the bristle ends.
[0036] The molten bristle ends are transported toward a location
where molten thermoplastic resin of composition compatible with the
composition of the monofilaments 155 (e.g., nylon, polypropylene,
or other suitable thermoplastic resin, including any of various
copolymers and/or blended mixtures thereof) emerges from the
extrusion die. The extrusion die is shaped so as to produce a brush
base 152 of suitable dimensions. For example, based upon
considerations related to ease of handling of individual strip
brush elements for creation of a flexible belt, the extruded brush
base 152 in one embodiment might be 2.5 mm to 6 mm in width, and
more preferably might be 3.2 mm to 4.5 mm in width. As the molten
bristle ends are brought into physical contact with the molten base
material as it emerges from the extrusion die, the bristle ends
fuse with the base 152 as the molten portion of the monofilaments
155 and the base 152 are made to blend together and molten base
material is made to flow around and fill interstices between
monofilaments 155. Note that if increased bonding strength and
increased bonding surface area are desired, this can be achieved by
carrying out more aggressive application of heat 105 so as to cause
more extensive melting of the bristle ends, as well as bonding of
bristle monofilaments 155 with each other, prior to fusion of the
melted bristle ends with the extruded base 152.
[0037] With continued reference to FIG. 4, at or about the time
that the monofilaments 155 and base 152 are fused together in the
vicinity of the extrusion die outlet, whereas the monofilaments 155
continue to travel in essentially the same direction in which they
had been traveling, the base 152 is made to undergo a 90-degree
change of direction so as to facilitate combination of the
monofilaments 155 with the base 152, following which the combined
monofilaments 155 and base 152 are then transported to a water bath
or other such cooling station 110 at which the molten, fused
material of the monofilaments 155 and the base 152 can be
solidified together.
[0038] Note that as used herein, the terms "melting" and "molten"
refer to creation of a liquid or soft state. That is, even where a
liquid state is not necessarily achieved, so long as the material
in question is soft enough to permit, blending, intermingling,
and/or fusion as described above, such a state is included within
the range of what is referred to herein as "melting" and
"molten."
[0039] Although the foregoing has been described in terms of an
example in which thermoplastic resin was used as material for the
brush base 152, there is no particular objection to employment of
thermosetting resin as base material. In the event that
thermosetting resin is employed as base material, one of skill in
that art will readily understand how to adapt the foregoing
description to a manufacturing method in which bristle
monofilaments 155, which may optionally be heated and made to melt
at one end, are fused with liquid (at least partially uncured)
thermosetting resin as it emerges from an extrusion die, with a
curing station being employed instead of cooling station 110.
[0040] Referring to FIG. 5, this shows a flexible strip brush
element 150 in a first embodiment such as might be manufactured
using the manufacturing method described with reference to FIG. 4.
A flexible belt brush of this design would have a flexural modulus
less than 80 ksi, preferably between 13 and 65 ksi, and more
preferably between 13 and 20 ksi, as determined for example by ASTM
D790. Such flexural moduli may be achieved by selection of suitable
material for use as the base 152. For example, a copolymer of nylon
and a suitable thermoplastic elastomer (hereinafter "TPE") may be
advantageously employed to achieve a base 152 having flexural
modulus within such ranges. This flexibility of the base material
permits manufacture of a brush having the ability to be constructed
into a belt, especially when a plurality of strip brush elements
are assembled in side-by-side fashion to form the belt.
[0041] As used herein, except where otherwise clear from context,
the term "belt" (and/or "belt brush") is used to mean a continuous
band for use in transferring motion or power, for use in cleaning,
for use in conveying objects or materials, or for use as a seal,
for example. As such, depending on the application in question,
belts manufactured in accordance with embodiments of the present
invention are able to take on many shapes and configurations as
required by the specific application. Examples of belt
configurations that may be manufactured in accordance with various
embodiments of the present invention include oval, serpentine,
reverse-directional, and figure-eight. Moreover, belts manufactured
in accordance with embodiments of the present invention may have
multiple radii along the length of the belt brush, and/or may have
the ability to conform to very small radii of curvature, e.g., on
the order of 0.25 inch or less, and still be able to maintain
flexibility. Various exemplary belt brush configurations
emphasizing this flexibility and versatility of belt brushes
manufactured in accordance with the present invention are shown at
FIGS. 13 through 15.
[0042] Note that where adjacent strips, or adjacent coils, are said
to be bonded in side-by-side fashion, this is not to imply that a
side bonding region (described below) need be used to accomplish
this. That is, side-by-side bonding may in general be carried out
through use of side bonding region(s) and/or bottom bonding
region(s), both of which are described in more detail below.
[0043] From the sectional end view shown in FIG. 5 it should be
understood that the flexible strip brush element 150 may take the
form of a linear section or may be fashioned into an endless loop
or jointless spiral. If fashioned in the form of a linear section,
this might be applied about the circumference of a shuttle canister
that opens in clamshell fashion, leaving a gap to permit the
canister to open, if used to slidably seal gaps between canister
and tube in a pneumatic tube transport system, or might be made to
engage in reciprocating motion by the mechanical components of a
suitable transport mechanism if used as a conveyor brush or
cleaning brush, for example. If fashioned in the form of an endless
loop or jointless spiral, this might be fitted over the end of an
end-opening shuttle canister if used to slidably seal gaps between
canister and tube in a pneumatic tube transport system, or might be
employed as a belt brush capable of being driven about pulleys and
idlers.
[0044] To fashion the flexible strip brush element 150 into an
endless loop, a linear section of the flexible strip brush element
150 of appropriate length would be prepared, and the two ends of
this linear section would be mated and bonded together using heat,
glue, or solvent, for example, to form a joint (see FIG. 7). Any
suitable type of joint, including lap joints, scarf joints, and
butt joints, may be used when the ends of the linear section are
joined to form an endless loop. Such joints may be unreinforced or
may be reinforced by sewing, stapling, crimping, or otherwise
binding across the seam of the joint using, for example, a suitable
high-strength fiber-like material, or cloth, tape, or plastic sheet
stock. Although there is no particular objection to use of metal
wire, staples or other such hard fasteners or materials to
reinforce the joint, especially for applications in which the belt
brush must go around corners or conform to tight radii of
curvature, e.g., when used as belt brush driven by pulleys or made
to wrap around idlers, softer materials such as cloth, tape, or
plastic sheet stock are generally preferred.
[0045] At this time, although there is no particular objection to
use of a butt joint in which the seam of the joint makes an angle
of 90 degrees with the sides of the belt, it may facilitate
formation of a smooth joint in some embodiments if the ends of the
linear section are cut at, for example, a 45 degree angle before
they are mated and bonded together so as to form a scarf joint in
which the length of the joint in the circumferential direction is
approximately equal to the width of the belt. Similarly, the ends
may be cut at a shallower angle before formation of the scarf joint
so as to increase the length of the joint in the circumferential
direction up to as much as the full circumference of the endless
loop belt.
[0046] Moreover, instead of joining the ends of a linear section of
the flexible strip brush element 150 to form an endless loop, it is
also possible to form the linear section into a jointless spiral by
wrapping such a linear section around a cylindrical mandrel in
helical fashion, and bonding adjacent coils of the spiral together
in side-by-side fashion, (see, e.g., FIG. 8).
[0047] At the flexible strip brush element 150 shown in FIG. 5, the
monofilaments 155 are attached at one end (the proximal end) to the
extruded base 152 to which they have been fused, the monofilaments
155 cooperating at their free ends (distal ends) 158 to form a
bristle end zone. Depending on the application in question, this
bristle end zone might serve as conveyor drive face capable of
nestling therewithin and carrying therealong small objects
including, but not limited to, nuts, bolts, pills, and/or other
such objects to be conveyed, might serve as cleaning brush for
cleaning parts or surfaces, or might serve as sealing surface
capable of sealing a shuttle canister within a pneumatic tube
transport system, for example. That is, the flexible strip brush
element 150 shown in FIG. 5 contains a multiplicity of brush
bristles or monofilaments 155 arranged in substantially parallel
fashion such that one end of each monofilament 155 is bonded to a
flexible base 152 and the other end 158 of each monofilament 155 is
free.
[0048] In one embodiment, the flexible base 152 to which the
monofilaments 155 are attached is capable of acting as a drive
belt. In such an embodiment, one side of the base 152 acts as
support for the monofilaments 155 that are attached thereto, while
the other side of the base 152 serves as a drive belt capable of
being driven by pulleys, idlers, or other such transport mechanism
drive components. In operation, when the belt side of the base 152
in such an embodiment is driven by an appropriate transport
mechanism, the free ends 158 of the monofilaments 155 cooperate to
form a bristle end zone.
[0049] The flexible strip brush element 150 in such an embodiment
might be employed as a belt brush such as a conveyor brush or
cleaning brush. For example, to form a conveyor brush, the ends of
a linear section of the flexible strip brush element 150 might be
joined after the fashion of an endless loop or jointless spiral.
This belt-driven conveyor brush could then be driven by the pulleys
and idlers of a transport mechanism. As the conveyor brush is
driven in this fashion, the bristle end zone collectively formed by
the free ends (distal ends) 158 of the monofilaments 155 of this
conveyor brush might cooperate to capture or grab and carry
therealong small objects including, but not limited to, nuts,
bolts, pills, and/or other such objects to be conveyed.
[0050] As another example, this flexible strip brush element 150
might be employed as a seal for sealing a shuttle canister within a
pneumatic tube transport system for use at a bank drive-up window.
To form such a shuttle canister seal, the ends of a linear section
of the flexible strip brush element 150 might be joined to form a
flexible belt brush in the form of an endless loop or jointless
spiral that is then fitted around and made to adhere to the outside
circumference of an end-opening shuttle canister. Alternatively, if
the shuttle canister opens in clamshell fashion, a linear section
of the flexible strip brush element 150 might be wrapped around and
made to adhere to the outside circumference of the shuttle canister
at all locations except for a gap to allow the shuttle canister to
open. This flexible belt brush could then form a seal between the
shuttle canister and the tube walls of the pneumatic tube transport
system so that the shuttle canister can be driven by air pressure
and/or vacuum. As the shuttle canister is driven within the
pneumatic tube transport system, the bristle end zone collectively
formed by the free ends (distal ends) 158 of the monofilaments 155
of the flexible strip brush element 150 might cooperate to form a
more or less airtight seal while allowing the shuttle canister to
move within the pneumatic tube transport system.
[0051] Referring to FIG. 6, another aspect of the present invention
is a flexible belt brush 100 containing one or more of the flexible
strip brush elements 150 described with reference to FIG. 5.
[0052] As shown by FIG. 6, a flexible belt brush 100 suitable for
slidably sealing gaps between canister and tube in a pneumatic tube
transport system or as a flexible belt brush in a conveyor or
cleaning application, for example, contains a plurality (here,
three) flexible strip brush elements 150 as described with
reference to FIG. 5. In the embodiment shown in FIG. 6, three
flexible strip brush elements 150 as shown in FIG. 5 are bonded
side-by-side by thermal bonding, glue, chemical bonding,
coextrusion, or any other suitable method. In bonding the flexible
strip brush elements 150 in side-by-side fashion, side bonding
region (s) and/or bottom bonding region(s) may be employed as
described below with reference to FIG. 11. In some embodiments, the
flexible belt brush 100 so formed is such that the bottoms of the
bases 152 cooperate to form a belt drive surface 130 capable of
being driven by a suitable transport mechanism. As was the case
with respect to description of the flexible strip brush element
150, the flexible belt brush 100 may take the form of a linear
section or may be fashioned into an endless loop or jointless
spiral. If fashioned in the form of a linear section, this might be
applied about the circumference of a shuttle canister that opens in
clamshell fashion, leaving a gap to permit the canister to open, if
used to slidably seal gaps between canister and tube in a pneumatic
tube transport system, or might be made to engage in reciprocating
motion by the mechanical components of a suitable transport
mechanism if used as a conveyor brush, for example. If fashioned in
the form of an endless loop or jointless spiral, this might be
fitted over the end of an end-opening shuttle canister if used to
slidably seal gaps between canister and tube in a pneumatic tube
transport system, or might be employed as a flexible belt brush
capable of being driven about pulleys and idlers. Moreover, in the
flexible belt brush 100 so formed, the free ends 158 of the
monofilaments 155 of the flexible strip brush elements 150
cooperate to form a bristle end zone 108. For example, if the
flexible belt brush 100 is employed as a conveyor brush, this
bristle end zone 108 might collectively form a single conveyor
drive face capable of nestling therewithin and carrying therealong
small objects including, but not limited to, nuts, bolts, pills,
and/or other such objects to be conveyed.
[0053] Where the flexible belt brush 100 is fashioned in the form
of an endless loop, it should be understood that formation of a
joint to mate the two ends of a linear section of the flexible belt
brush 100 may be carried out in the same manner as described above
with reference to the flexible strip brush element 150 of FIG. 5.
An example in which a flexible belt brush similar to the flexible
belt brush 200 described below with reference to FIG. 11 contains
three flexible strip brush elements 250 has been fashioned in the
form of an endless loop through use of a joint to mate the ends of
a linear section thereof are shown at FIG. 7. The example shown in
FIG. 7 depicts a 90-degree butt joint and a 45-degree miter (scarf)
joint, and of course there is no objection to employment of any
other suitable type of joint, such as an overlap joint.
[0054] Moreover, it should be understood that, like the flexible
strip brush element 150 described above with reference to FIG. 5,
the flexible belt brush 100 may be fashioned in the form of a
jointless spiral, and that where this is done, the manner in which
it may be carried out is similar to the description given above
with reference to the flexible strip brush element 150 of FIG. 5.
An example in which a single long flexible strip brush element 150
has been fashioned in the form of a jointless spiral by wrapping a
linear section similar to that shown in FIG. 5 around a cylindrical
mandrel in helical fashion is shown at FIG. 8.
[0055] For example, in a first working example, using four flexible
strip brush elements 150 that were each approximately 4.5 mm in
width and that were manufactured from a nylon-TPE copolymer base
152 and nylon monofilaments 155 of diameter 0.2 mm, a flexible belt
brush 100 that was approximately 18 mm in width was fabricated by
bonding the flexible strip brush elements 150 together in
side-by-side fashion by heat-welding to melt and resolidify the
bases 152, this then being made into a flexible belt brush 100 in
the form of an endless loop by means of a glued joint, in which the
ends were cut at a 45 degree angle, the two ends being sewn
together using #21 gauge steel wire prior to application of
cyanoacrylate adhesive as glue so as to form a wire-reinforced
joint. The flexible belt brush 100 so formed was approximately 18
mm wide.times.30 mm high.times.480 mm in diameter. The flexible
belt brush 100 of this first working example was found to perform
satisfactorily for conveying objects of 0.25 inch diameter and
larger, as well as flat objects such as a penny, or for cleaning
the surface of a metal plate.
[0056] Moreover, in a second working example, using seven flexible
strip brush elements 150 that were each 4.5 mm in width and that
were manufactured from a nylon-TPE copolymer base 152 and nylon
monofilaments 155 of diameter 0.006 inch, a flexible belt brush 100
of 0.89 inch width.times.0.28 inch height was fabricated by bonding
the flexible strip brush elements 150 together in side-by-side
fashion by heat-welding to melt and resolidify the bases 152, this
then being made into a flexible belt brush 100 in the form of a
linear section that was 19 inches in length and 0.28 inch in height
for employment in a shuttle-type pneumatic tube transport
apparatus. The flexible belt brush 100 of this second working
example was found to perform satisfactorily for sealing a shuttle
canister within a pneumatic tube transport apparatus.
[0057] FIG. 9 shows a flexible strip brush element 250 in a second
embodiment such as might be manufactured using a manufacturing
method similar to that described with reference to FIG. 4. The
manufacturing method used to fabricate the flexible strip brush
element 250 of the second embodiment shown in FIG. 9 is similar to
the manufacturing method used to fabricate the flexible strip brush
element 150 of the first embodiment shown in FIG. 5, except that
the extrusion die employed for extrusion of the flexible strip
brush element 250 of the second embodiment shown in FIG. 9 is
shaped so as to cause the base 256 to have a channel-like, or
U-shaped, cross-section. Employment of a base 256 having
channel-like or U-shaped cross-section may, for example, provide
additional structure at the base 256 that holds the monofilaments
255 for easier handling and assembly. Although the channel-like
profile of this base 256 is shown in somewhat exaggerated fashion
in FIG. 9, note as was mentioned above when discussing the prior
art that excessive height is not preferred in the channel-like base
256 from the standpoint of lowering second moment of inertia and
improving flexibility with respect to bending of the flexible strip
brush element 250 in such fashion as to form an endless loop or
jointless spiral therefrom. Except for the different shape of the
base 256, structure and function of the flexible strip brush
element 250 of the second embodiment shown in FIG. 9 being similar
to the structure and function of the flexible strip brush element
150 of the first embodiment shown in FIG. 5, like parts are
therefore given like-numbered reference numerals and description
thereof is omitted for brevity.
[0058] Conversely, except where otherwise clear from context,
description given below with reference to the flexible strip brush
element 250 shown in FIGS. 9 and 10A, and with reference to the
flexible belt brush 200 assembled therefrom shown in FIG. 11, may
be understood to apply as well to the flexible strip brush element
150 shown in FIG. 5 and to the flexible belt brush 100 assembled
therefrom shown in FIG. 6. In particular, description of the
bristle attachment region 257 shown in FIGS. 9 through 11, of the
side-to-side bonding region 220 shown in FIG. 11, and of the belt
drive surface 230 shown in FIG. 11, although not shown or described
to the same extent during description of the embodiments shown in
FIGS. 5 and 6, may nonetheless be understood to apply as well to
the embodiments shown in FIGS. 5 and 6.
[0059] Referring to FIG. 10A, this is an end sectional view of the
flexible strip brush element 250 of the second embodiment shown in
perspective view in FIG. 9. As shown by FIG. 10A, the flexible
strip brush element 250 contains a multiplicity of brush bristles
or monofilaments 255 arranged in substantially parallel fashion
such that one end of each monofilament 255 is bonded to a flexible
channel-like base 256 and the other end of each monofilament 255 is
free. In some embodiments, the base 256 to which the monofilaments
255 are attached is capable of acting as a drive belt. In some
embodiments, the concave side of the channel-like base 256 acts as
support for the monofilaments 255 that are attached thereto, while
the bottom of the channel-like base 256 serves as a drive belt
capable of being driven by pulleys, idlers, or other such transport
mechanism drive components. For example, in an application in which
the flexible strip brush element 250 is employed as a conveyor
brush, the belt side of the base 256 is driven by an appropriate
transport mechanism and the free ends of the monofilaments 255
cooperate to capture or grab and carry therealong small objects
including, but not limited to, nuts, bolts, pills, and/or other
such objects to be conveyed. As mentioned above, especially where
the flexible strip brush element 250 is to be formed into an
endless loop or jointless spiral, it is preferred that channel
height 290 not be too large, so as to permit good flexibility.
Exemplary dimensions for the channel-like base 256 might be such
that channel height 290 is on the order of between 2.5 mm and 5 mm
or more, and channel width is on the order of between 2.5 mm and 6
mm or more.
[0060] Also visible at FIG. 10A is the bristle attachment region
257. The bristle attachment region 257, being the region at which
the monofilaments 255 are attached to the base 256, is the location
at which molten monofilament material blended with molten base
material, and/or where molten base material was made to flow around
and fill interstices between monofilaments, during fusion of the
monofilaments 255 with the extruded base 256 (taking the case where
thermoplastic resin is used as material for extrusion of the base
256, the method by which the monofilaments 255 are fused to the
base 256 being substantially as described above with reference to
FIG. 4). As such, at this bristle attachment region 257, there is
chemical and/or physical intermingling of the monofilament material
and the base material. After the molten thermoplastic material in
the bristle attachment region 257 is allowed to cool following
extrusion and fusion, this blending and/or intermingling of
material at the interface of the monofilaments 255 and the base 256
permits the monofilaments 255 to be held firmly to the base 256
without the need for staples or other such fasteners. Moreover,
because there is no need to use staples or other such fasteners,
monofilaments 255 can be arranged with uniform density and without
discontinuity in any desired density. Furthermore, manufacturing is
greatly simplified, as there is no need to drill or mold holes, or
to insert monofilament tufts within such holes, or to staple or
otherwise fasten such monofilament tufts within such holes.
Moreover, elimination of the need to staple monofilament tufts
within holes makes it possible to greatly reduce the thickness in
the height direction of the base 256, and notwithstanding that the
channel height 290 is shown in somewhat exaggerated fashion in FIG.
10A there is no particular objection to reducing channel height 290
so that the base 256 of the second embodiment shown in FIG. 10A
approaches a configuration resembling that of the first
configuration shown in FIG. 5. For example in an embodiment in
which the flexible strip brush element 250 is to be used as a
conveyor brush, the base 256 need be only as thick as is required
for the drive belt surface at the bottom and the bristle attachment
region 257 at the top. Such a flexible strip brush element 250 will
exhibit good flexibility with respect to flexure about an axis
perpendicular to the plane of the bristles 255, such as would be
desired were the flexible strip brush element 250 to be fashioned
in an endless loop or jointless spiral for driving by pulleys and
idlers.
[0061] As was the case with the flexible strip brush element 150
shown in FIG. 5, the flexible strip brush element 250 shown in
FIGS. 9 and 10A may employed as a flexible belt brush 200 in the
form of a linear section or may be fashioned into an endless loop
or jointless spiral. If fashioned in the form of a linear section,
this might be applied about the circumference of a shuttle canister
that opens in clamshell fashion, leaving a gap to permit the
canister to open, if used to slidably seal gaps between canister
and tube in a pneumatic tube transport system, or might be made to
engage in reciprocating motion by the mechanical components of a
suitable transport mechanism if used as a conveyor brush or
cleaning brush, for example. If fashioned in the form of an endless
loop or jointless spiral, this might be fitted over the end of an
end-opening shuttle canister if used to slidably seal gaps between
canister and tube in a pneumatic tube transport system, or might be
employed as a flexible belt brush capable of being driven about
pulleys and idlers. Furthermore, a plurality of flexible strip
brush elements 250 as shown in FIGS. 9 and 10A may be combined in
side-by-side fashion to form a flexible belt brush 200 of any
desired width.
[0062] FIG. 10B illustrates an alternative embodiment of an end
sectional view of the flexible strip brush element 250 of the
second embodiment shown in perspective view in FIG. 9. As shown in
FIG. 10B, the base 256 is extended along the sides of the brush
element 250 both above and below the plane of the proximal ends of
the bristles 255. The extension below the plane of the proximal
ends of the bristles 255 forms a rib 258.
[0063] The manufacturing method used to fabricate the flexible
strip brush element 250 of the alternative embodiment shown in FIG.
10B is similar to the manufacturing method used to fabricate the
flexible strip brush element 150 of the first embodiment shown in
FIG. 5, except that the extrusion die employed for extrusion of the
flexible strip brush element 250 of the second embodiment shown in
FIG. 9 is shaped so as to cause the base 256 to have a
channel-like, or H-shaped, cross-section. Employment of a base 256
having channel-like or H-shaped cross-section may, for example,
provide additional structure at the base 256 that holds the
monofilaments 255 for easier handling and assembly. The ribs 258
may also improve the welding process for the backside of the belt
when bonding multiple strip brush elements 250 together, as
described below. Exemplary dimensions for the ribs 258 might be
such that rib height is up to 2 mm or more, and having a preferred
rib height of approximately 0.5 mm. Except for the different shape
of the base 256, structure and function of the flexible strip brush
element 250 of the alternative embodiment shown in FIG. 10B being
similar to the structure and function of the flexible strip brush
element 150 of the first embodiment shown in FIG. 5, like parts are
therefore given like-numbered reference numerals and description
thereof is omitted for brevity.
[0064] It should be noted that while FIG. 10B shows ribs 258
deployed in conjunction with a channel-like base 256 where the
channel height 290 (FIG. 10A) is larger than the height of the ribs
258, in other embodiments (not shown) the channel height 290 may be
equal or smaller than the height of the ribs 258. In other
embodiments (not shown) the ribs 258 may be present in the absence
of a channel in base 256.
[0065] FIG. 11 illustrates an end sectional view of a flexible belt
brush 200 suitable for slidably sealing gaps between canister and
tube in a pneumatic tube transport system or as a flexible belt
brush in a conveyor or cleaning application, for example. The
flexible belt brush 200 shown in FIG. 11 contains a plurality
(here, three) of flexible strip brush elements 250 as described
with reference to FIGS. 9 and 10A. In the embodiment shown in FIG.
11, three flexible strip brush elements 250 as shown in FIGS. 9 and
10A are bonded side-by-side by thermal bonding, glue, chemical
bonding, coextrusion, lamination, or any other suitable method. In
bonding the flexible strip brush elements 250 in side-by-side
fashion, side bonding region(s) 220 and/or bottom bonding region(s)
230 may be employed as described below. In some embodiments, the
flexible belt brush 200 so formed is such that the bottoms of the
bases 256 cooperate to form a belt drive surface capable of being
driven by a suitable transport mechanism. As with the flexible belt
brush 100 described with reference to FIG. 6, the flexible belt
brush 200 shown in FIG. 11 may take the form of a linear section or
may be fashioned into an endless loop or jointless spiral. If
fashioned in the form of a linear section, this might be applied
about the circumference of a shuttle canister that opens in
clamshell fashion, leaving a gap to permit the canister to open, if
used to slidably seal gaps between canister and tube in a pneumatic
tube transport system, or might be made to engage in reciprocating
motion by the mechanical components of a suitable transport
mechanism if used as a conveyor brush, for example. If fashioned in
the form of an endless loop or jointless spiral, this might be
fitted over the end of an end-opening shuttle canister if used to
slidably seal gaps between canister and tube in a pneumatic tube
transport system, or might be employed as a flexible belt brush
capable of being driven about pulleys and idlers. Moreover, in the
flexible belt brush 200 so formed, the free ends of the
monofilaments 255 of the flexible strip brush elements 250
cooperate to form a bristle end zone. For example, if the flexible
belt brush 200 is employed as a conveyor brush, this bristle end
zone might collectively form a single conveyor drive face capable
of nestling therewithin and carrying therealong small objects
including, but not limited to, nuts, bolts, pills, and/or other
such objects to be conveyed.
[0066] In forming the flexible belt brush 200 shown in FIG. 11 from
three flexible strip brush elements 250 as shown in FIGS. 9 and
10A, adjacent flexible strip brush elements 250 may, for example,
be bonded together by means of side bonding regions 220. These side
bonding regions 220 may be formed using heat, glue, solvent,
coextrusion, or any other suitable method. In some embodiments,
presence of these side bonding regions 220 alone is sufficient to
mechanically join adjacent flexible strip brush elements 250. That
is, although a separate bottom bonding region 230 is shown in FIG.
11, and an example is described below in which such a separate
bottom bonding region 230 is formed through coextrusion,
lamination, melting and reforming, or dissolving and resolidifying,
of the area through application of glue, heat, solvent, or other
suitable method, in some embodiments there is no need for such a
separate bottom bonding region 230. That is, where there is no need
for such a separate bottom bonding region 230, this can be
interpreted to mean that the thickness 295 of the bottom bonding
region 230 is zero. For example, in an application in which the
flexible belt brush 200 is employed as a belt brush in a conveyor
or similar transport application, a thickness 295 of zero at the
bottom bonding region 230 should be interpreted to mean that the
bottoms of the bases 256 of the flexible strip brush elements 250
themselves cooperate to form a belt drive surface capable of being
driven about pulleys and idlers. Alternatively or in addition to
one or more side bonding regions 220, adjacent flexible strip brush
elements 250 may be bonded together by means of a bottom bonding
region 230. This bottom bonding region 230 may be formed using
heat, glue, solvent, coextrusion, lamination, or any other suitable
method. In some embodiments, presence of this bottom bonding region
230 alone is sufficient to mechanically join adjacent flexible
strip brush elements 250. That is, although side bonding regions
220 are shown in FIG. 11, and an example is described above in
which such side bonding regions 220 are formed through coextrusion,
lamination, melting and reforming, dissolving and resolidifying,
and/or through application of glue, heat, solvent, or other
suitable method, in some embodiments there is no need for such side
bonding regions 220, the presence of the bottom bonding region 230
alone being sufficient to hold the flexible strip brush elements
250 together in side-by-side fashion. Moreover, in an application
in which the flexible belt brush 200 is employed as a belt brush in
a conveyor or similar transport application, the bottom surface of
the bottom bonding region 230 may serve as a belt drive surface
capable of being driven about pulleys and idlers.
[0067] For example, where heat is employed to form a bottom bonding
region 230, the zone indicated with reference numeral 230 at FIG.
11 might be a zone in which application of heat caused the bottoms
of the bases 256 to melt together, this then being made to
resolidify in this configuration upon cooling. In some embodiments,
the side bonding regions 220 may be absent, this bottom bonding
region 230 alone being sufficient to bond flexible strip brush
elements 250 together in side-by-side fashion, and in some
embodiments the zone indicated with reference numeral 220 at FIG.
11 might be a zone in which hot base material, this base material
having melted due to application of heat in forming the bottom
bonding region 230, flows into the spaces between adjacent flexible
strip brush elements 250, and the side bonding regions 220 so
formed are also made to resolidify in this configuration upon
cooling. That is, in some embodiments in which there is
substantially only a bottom bonding region 230, there is
nevertheless the possibility that there may be some wicking or
unintended flow of excess or residual material from the bottom
bonding region into the space between channel sides, but without
significant mechanical effect or contribution to bonding strength
between adjacent strip brush elements 250. Furthermore, in some
embodiments, reference numeral 230 at FIG. 11 might be interpreted
to indicate a separate carrier strip of suitable material (e.g.,
flexible thermoplastic resin such as nylon or polypropylene) that
is bonded to the bottoms of the bases 256 of the flexible strip
brush element 250 by means of heat, glue, solvent, coextrusion,
lamination, or any other suitable method to form the bottom bonding
region 230.
[0068] Where the strip brush elements 250 forming the flexible belt
brush 200 shown in FIG. 11 are configured as per the alternative
embodiment shown in FIG. 10B where the base 256 includes ribs 258,
the ribs 258 may facilitate the formation of the bottom bonding
region 230 (FIG. 11). In such an alternative embodiment, heat may
be applied to ribs 258, causing the material of ribs 258 to melt
and flow onto the back of the brush beside ribs 258, thereby
forming the bottom bonding region 230. In such an alternative
embodiment, the melted rib material may entirely form the bottom
bonding region 230, or the bottom bonding region 230 may be further
supplemented with additional material. Such additional material may
be added by melting the material so it flows and solidifies over
bottom bonding region 230, or may instead be laminated over the
material of melted ribs 258. When ribs 258 are heated and melted,
the height of ribs 258 may be somewhat reduced, forming a smaller,
residual rib, or the ribs 258 may be entirely reduced so that the
ribs 258 are removed and the rib material is entirely reformed into
the bottom bonding region 230.
[0069] Moreover, although in the foregoing description side bonding
regions 220 were described as plural and a bottom bonding region
230 was described as singular, there is no particular objection to
combining use of side bonding region(s) 220 and/or bottom bonding
region(s) 230 in any desired combination. For example, in an
embodiment in which a flexible belt brush is fabricated from, for
example, three flexible strip brush elements, a side bonding region
220 might be used to bond one pair of adjacent strip brush elements
while a bottom bonding region 230 might be used to bond the other
pair of adjacent strip brush elements. As another example, in an
embodiment in which a flexible belt brush is fabricated from, for
example, four flexible strip brush elements, a side bonding region
220 might be used to bond the central pair of adjacent strip brush
elements while bottom bonding regions 230 might respectively be
used to bond the pairs of adjacent strip brush elements to either
side of the central pair of adjacent strip brush elements, or
vice-versa.
[0070] In the foregoing description, application of heat is
employed to form side bonding region(s) 220 and/or bottom bonding
region(s) 230 for holding flexible strip brush elements 250
together in side-by-side fashion to form a flexible belt brush 200
of width greater than the width of a single flexible strip brush
element 250. However, glue, solvent, coextrusion, or any other
suitable method may be employed to form side bonding region(s) 220
and/or bottom bonding region(s) 230 for joining flexible strip
brush elements 250 in side-by-side fashion. The procedure being
similar regardless of the method employed for forming side bonding
region(s) 220 and/or bottom bonding region(s) 230, and description
having been given in exemplary fashion for use of heat to form side
bonding region(s) 220 and/or bottom bonding region(s) 230, detailed
description of other methods is omitted for brevity.
[0071] Referring to FIG. 12, this shows a method for manufacturing
a flexible belt brush 200 similar to that shown in FIG. 11 from
three flexible strip brush elements 250 similar to the flexible
strip brush element 250 shown in FIGS. 9, 10A and 10B. In
accordance with the method depicted in FIG. 12, heat is employed to
reflow, or melt and resolidify, the material of the bases 256 of
the strip brush elements 250 so as to form a bottom bonding region
230. During formation of the bottom bonding region 230, application
of heat causes the bottoms of the bases 256 to melt together, the
molten bases then being made to resolidify in a fused configuration
upon cooling. In the embodiment shown, there is substantially only
a bottom bonding region 230 and no side bonding region 220, except
to the extent that wicking or capillary-like flow of excess or
residual molten material from the bases or bottom bonding region
230 flows into the spaces between channel sides. However, in the
embodiment shown, presence of such insignificant amount of material
between channel sides would not be understood to qualify as a side
bonding region 220 unless it were to have significant mechanical
effect or contribution to bonding strength between adjacent strip
brush elements 250. In FIG. 12, it should be noted that a shoe-like
tool 1200 that has been coated with Teflon.RTM. (registered
trademark of E.I. du Pont de Nemours and Company, of Delaware USA)
or other such nonstick material (e.g., any of the substances
commonly employed, for example, as mold release agent may
alternatively or in addition be used) is used in combination with a
hot air gun (not shown) or other suitable source of heat to reflow
the base material in controlled fashion as the heated nonstick tool
is pressed against the bottom surfaces of the bases with
appropriate pressure while the tool 1200 is dragged therealong at a
suitable relative speed as will cause reflow to an appropriate
depth. At this time, use of such a nonstick tool 1200 facilitates
manipulation of the otherwise unwieldy molten material, since the
flexible materials preferably employed as base material tend to
become quite soft and gooey when heated.
[0072] Where the strip brush elements 250 being bonded are of the
alternative embodiment shown in FIG. 10B where the base 256
includes ribs 258, the ribs 258 may further facilitate and
strengthen the formation of the bottom bonding region 230. When two
or more brush elements 250 are placed side by side, the shoe-like
tool 1200 of FIG. 12 is applied to the bottom region and the
shoe-like tool will initially come in contact with ribs 258,
causing the ribs 258 to melt and flow onto the back of the brush.
The material from the melted ribs 258 is added to the back of the
brush, thereby forming the bottom bonding region 230 and adding to
the overall thickness of the brush and thus strengthening the belt.
Further, the thin width of the ribs 258 allows the material of ribs
258 to melt and begin to flow more quickly upon application of heat
from the shoe-like tool than the material of an embodiment without
ribs 258, such as the embodiment shown in FIG. 10A.
[0073] Where a strip brush element such as that shown in FIG. 5 or
FIGS. 9, 10A and 10B, or a strip brush such as that shown in FIG. 6
or FIG. 11, is wrapped around a mandrel in helical fashion to form
a jointless spiral, adjacent coils of the helical spiral may be
bonded in side-by-side fashion in substantially the same manner as
has been described above for bonding of adjacent strips. For
example, side-by-side bonding may in such case be carried out
through use of side bonding region(s) and/or bottom bonding
region(s). As this has been described in detail in connection with
bonding of adjacent strips, description in connection with bonding
of adjacent coils is omitted for brevity.
[0074] FIGS. 13 through 15 show various exemplary belt brush
configurations emphasizing the flexibility and versatility of the
flexible belt brushes that may be manufactured in accordance with
embodiments of the present invention, the flexible belt brush at
FIG. 13 being shown in a configuration intended to emphasize the
superior flexibility thereof with respect to flexure about an axis
perpendicular to the plane of the bristles, and the flexible belt
brushes at FIGS. 14 and 15 being shown in configurations intended
to emphasize the superior flexibility thereof with respect to
flexure as well as torsion.
[0075] A flexible belt brush containing one or more flexible strip
brush elements as described above overcomes one or more
inadequacies of the prior art and/or has other benefits and
advantages. It should be emphasized that the above-described
embodiments of the present invention are merely possible examples
of implementations, merely set forth for a clear understanding of
the principles of the invention. Many variations and modifications
may be made to the above-described embodiments of the invention
without departing substantially from the spirit and principles of
the invention. All such modifications and variations are intended
to be included herein within the scope of this disclosure and the
present invention and protected by the following claims.
* * * * *