Note: Descriptions are shown in the official language in which they were submitted.
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TITLE OF THE INVENTION
Broom and method of fabrication thereof
FIELD OF THE INVENTION
[0001] The present invention relates to a broom head or brush, and a
method of fabrication
thereof.
SUMMARY OF THE DISCLOSURE
[0002] More specifically, in accordance with the present disclosure,
there is provided a method
comprising molding a shell having a top surface and a bottom surface, the
bottom surface comprising a
pattern of housings, the housings being selectively localised and inclined
relative to a direction normal to
a plan of the shell depending on a position along a length and across a width
of the bottom surface;
finishing the housings of the as-molded shell into sockets; and securing tufts
of bristles within the sockets.
[0003] There is provided a method of fabrication of an angled-bristled
tool head, comprising
molding a shell comprising a pattern of housings selectively localised and
inclined relative to a direction
normal to a plan of the shell; finishing the housings of the as-molded shell
into sockets; and tufting bristles
within the sockets.
[0004] There is provided a one-piece molded bristled tool head,
comprising a top surface and
a bottom surface, wherein said bottom surface comprises a pattern of sockets
selectively localised and
inclined relative to a direction normal to a plan of the tool head depending
on a position along a length
and across a width of the bottom surface, and tufts of bristles secured within
the sockets.
[0005] Other objects, advantages and features of the present
disclosure will become more
apparent upon reading of the following non-restrictive description of specific
embodiments thereof, given
by way of example only with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] In the appended drawings:
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[0007] FIG. 1 is a front perspective view of a broom according to an
embodiment of an aspect
of the disclosure;
[0008] FIG. 2 is a detail of a broom head according to an embodiment
of an aspect of the
disclosure;
[0009] FIG. 3 is an underside view of a shell for a broom head
according to an embodiment of
an aspect of the disclosure;
[0010] FIG. 4 is an underside view of a shell for a broom head
according to an embodiment of
an aspect of the disclosure;
[0011] FIG. 5 is a side view of a shell for a broom head according to
an embodiment of an
aspect of the disclosure;
[0012] FIG. 6A is a partial underside view of a shell for a broom head
according to an
embodiment of an aspect of the disclosure;
[0013] FIG.6B is a cross section of FIG. 1A;
[0014] FIG. 7A is a cross section of pre-sockets of an as-molded shell
for a broom head, with
a socket shape shown in phantom lines, according to an embodiment of an aspect
of the disclosure;
[0015] FIG. 7B is a cross section of sockets of a shell for a broom
head according to an
embodiment of an aspect of the disclosure;
[0016] FIG. 70 is a cross section of sockets of a shell fora broom
head;
[0017] FIG. 8A and FIG 8B show bristles according to an embodiment of
an aspect of the
disclosure; and
[0018] FIG. 9 shows sections of broom heads of the art compared to of
a broom head according
to an embodiment of an aspect of the disclosure.
DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0019] The present invention is illustrated by the following non-
limiting examples.
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[0020] FIG. 1 shows a broom 10 comprising a broom head 12 connected at
a distal end of a
handle 14, by a bracket 16 for example.
[0021] The broom head 12 comprises a working surface, generally
indicated as 18 in FIG. 1,
opposite the handle 14, providing a contact and brushing surface with a
surface to be swept. The brushing
surface 18 comprises bristles 20, supported on the underneath of the broom
head 12 by a shell 22.
[0022] FIGs. 3 to 7 show the shell 22 according to an embodiment of an
aspect of the
disclosure.
[0023] The shell 22 is molded as a single piece of a length (L) and a
width (I) (FIG. 4). The shell
22 comprises a top surface 24 and a bottom surface 26. The shell 22 may be
molded in PP, PEND, ABS
for example.
[0024] The top surface 24 is generally flat; a slight convexity is
shown in FIGs. 1 or 5 for
example. A bracket 16 as shown in FIG.1 may be used for connection between the
handle 14 and the top
surface 24 of the broom head 12.
[0025] As best seen in FIGs. 3, 4 and 6 for instance, the bottom
surface 26 comprises a pattern
of molded housings 42, referred to herein as pre-sockets. The pre-sockets 42
are selectively localised,
and inclined relative to the normal (V) to the plan of the shell 22; the
longitudinal axis of each pre-socket
42 has a selected angle relative to this axis (V) perpendicular to the bottom
surface 26, depending on its
position along the length (L) and across the width (I) of the broom head (see
for example angles 01, 02
in FIG. 6B).
[0026] The depth of each presocket relative to the height (t) of the
shell 22 is selected in relation
to its respective inclination angle relative to the normal (V) to the plan of
the shell 22 so that the shell 22
may be demolded, i.e. without undue bending effect for example. The
inclination angle of the presockets
relative to the normal (V) to the plan of the shell 22 is typically comprised
in a range between about 0 and
about 30 . When thus molded and removed from the mold, the shell 22 is a thin,
essentially hollow, one-
piece molded part having a top surface and a bottom surface separated by of a
maximum height (t), and
comprising a pattern of presockets on the bottom surface, thereby comprising a
minimised amount of
molded material.
[0027] The as-molded shell 22 is then positioned in a tufting machine,
the bottom surface 26
thereof facing the tufting head. In a first pass of the tufting head, the pre-
sockets 42 (FIG. 7A) are drilled
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into sockets 50 (FIG. 7B; and FIG.7A in phantom line) of an inclination angle
depending on the position
along the length and across the width of the broom head. Sockets 50 as shown
in FIG. 7B have a depth
allowing constrainingly securing tufts 20 of bristles 20 (see for instance
FIG. 8b as opposed to FIG. 8A
for example), each at a precise position and angle, in following passes of the
tufting head. Such depths
of the sockets, depending on their angle, could not be molded in the first
place. Once the tufts 33 are
clamped to the bottom of the sockets 50, in the thickness (t2) of material of
the shell underneath the
socket as shown in FIG. 6B for example, the top surface 24 of the broom head
is free of any marks due
to the clamping of the bristles.
[0028] The bristles 20 may be made of natural fibers, such as such as
Palmyra for example, or
synthetic or polymeric fibers, such as Nylon for example. The number and/or
density and/or diameter
and/or length of the bristles 20 and the inclination angles of the bristles 20
across the bottom surface 26
of the tool head are selected depending on a target firmness or stiffness of
the brushing surface of the
broom head.
[0029] Fibers 30 may be folded into tufts 33 as shown in FIGs. 8A, 8B
for instance, then a tuft
33 as shown in FIG. 8B is inserted within a socket 50 and clamped to a bottom
of the socket 50 (in the
thickness (t2) of material of the shell underneath the socket as shown in FIG.
6B for example) using a
clamp 32 for instance.
[0030] As best seen in FIGs. 6, each socket 50 has an angle selected
depending on its location
along the length and across the width of the broom head (see for example FIG.
6B). The thickness of the
wall of the broom head is minimised, with a larger thickness underneath the
sockets 50 allowing clamping
of the tufts at the bottom of the sockets 50 (see FIG. 6B t2 larger than ti).
[0031] FIG. 7A shows a pre-socket 42, which may be finished into a
socket 50 according to an
embodiment of an aspect of the present disclosure as shown in FIG. 7B. As
people in the art will
appreciate, sockets of a depth and inclination angle as shown in FIGs. 7B or
70 cannot be molded as
demolding issues arise from the inclination angle and undercuts resulting from
the selected geometry,
which is not an issue in case of sockets with a longitudinal axis aligned with
the normal (V) to the plan of
the shell 22.
[0032] Bristles may be more inclined relative to the direction (V)
perpendicular to the plane of
the broom head as they are positioned closer to the edges of the broom head
(see for example FIG. 6B).
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[0033] A range of tufts pattern configuration may be selected, by
selecting the rigidity, the
inclinations angles, the length, the diameter, the cross section, the
coloring, and /or the density of the
bristles and/or tufts for example. Patterns may include rows aligned with an
edge of the shell.
[0034] The broom head may be connected to the handle as discussed
hereinabove, thereby
forming a broom (see FIG. 1 for instance); it may alternatively be used as a
hand brush.
[0035] A minimum amount of molded material is used to form the present
tool head by molding
the shell including presockets.
[0036] In contrast to broom heads of the art typically being massive
blocks of material, the
present tool head surface is a molded one-piece shell provided with sockets
(FIG. 9, right hand side).
Molding cycles are shortened due to thin walls of the shell, as cooling time
is minimized. The present tool
head has a reduced weight, typically from 600 g in the art down to 300 g for
example.
[0037] The scope of the claims should not be limited by the
embodiments set forth in the
examples, but should be given the broadest interpretation consistent with the
description as a whole.
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