Note: Descriptions are shown in the official language in which they were submitted.
DUVET COVER WITH REMOVABLE DOWN FEATHER SHEET
This application is related to Canadian Application No.2,882,023 filed on
March 16,
2015 and entitled Duvet Cover With Down Feather Sheet.
TECHNICAL FIELD
(0001) The present invention relates to duvet covers and more particularly to
a duvet
cover having a pouch having attachments inside to removably retain a flat down
thermally insulating sheet of substantially constant thermal efficiency, or
fill power and
which is removed from the pouch when it is necessary to wash the pouch to
prevent
the down insulating sheet from being washed and tumbled dried.
BACKGROUND OF THE INVENTION
(0002) Duvet covers having down insulation trapped between the base sheet and
top
sheet of the duvet cover are well known in the art. It is also well known that
down
feathers provide excellent insulating properties. The higher the fill power
(fluffiness ) of
the down and therefore the more air trapped in the down, the more insulating
ability
an ounce of the down will have. Down is also a very light product that is
desirable for
insulation and particularly with products wherein weight is a factor, such as
articles of
apparel, sleeping bags, duvet covers, etc. However, down is a difficult
product to work
with due to its fluffy nature and unstable condition. It can also be hazardous
to one's
health has its fluffy miniscule filaments easily propagate into the
surrounding air. For
this reason work personnel are advised to wear breathing masks.
(0003) Articles of apparel and bedding manufactured with down feather
insulation are
constructed by entrapping the down between opposed fabric sheets. To prevent
the
down from displacement, the fabric sheets are sewn with quilt stitched
patterns. Some
of these patterns are produced by cross-stitches to form small pockets in
which the
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down feathers are trapped. See US Patent 5,692,245 as an example. With bedding
products, such as a duvet cover, the quilt stitches may be spaced apart from
about 1
inch to 10 inches forming pockets with loose down therein. During use of these
products, the down shifts within the pockets and form areas where the down is
concentrated and other areas where there is much less down or no down. This
results
in areas where there is too much insulation or not enough insulation.
Furthermore,
because the down is loose between the fabric sheets at the time of stitching,
the down
is not uniformly distributed between the fabric sheets resulting in stitching
being done
over heavy down underlay or no down at all creating irregularities in the
stitched
seams which are visible to the eye or resulting in a rejection of the
manufactured
product. Because duvet covers are made with large cross stitched quilt
patterns and
consequently large pockets for retaining the down, the down will propagate to
corners
of these pocket and unevenly therein. In the case of duvet covers having no
quilt
stitches, the down always propagate into regions and it is then necessary to
shake the
duvet in an attempt to distribute the down substantially evenly therein but
such is
near to impossible. Accordingly, the duvet cover has to be shaken constantly
due to
the unstable nature of the down.
(0004) A further problem with duvet covers is that when they are washed, the
loose
feathers or down absorbs water and the mechanical action of a drying machine
is not
desirable for the down as the duvet cover is subjected to a tumbling and
stretching
action. Therefore, it is best to let the duvet cover dry in the open air to
maintain a
duvet cover with a uniform appearance. Dry cleaning is an option which is more
costly
and also is not desirable down duvet covers. Accordingly, the useful life of
the duvet
cover is reduced when subjected to washing and drying
(0005) There is also a need to have a duvet cover wherein the thermal
insulation
factor can be modified throughout the duvet cover or in designated parts
thereof to
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suit individual preferences and/or calibrate the insulation of the duvet cover
to the
changing seasons.
(0006) US Patent 6,025,041 addresses the problem of using the loose fluffy
down
feathers in the manufacture of articles and relates to a method of forming a
down
feather sheet of substantially constant thickness and particularly for use in
the
fabrication of articles of apparel such as described in US Patent 5,692,245.
(0007) It is also desirable with duvet covers to provide different thermal
properties for
each sleeping side of a bed, as is described and demonstrated in US Patent
Publication
2005/0268399. It is also well known that the body of a person, when sleeping,
requires
less covering and thermal insulation in certain sections of its body.
(0008) It would also be desirable to manufacture light weight duvet covers
having
esthetically pleasing stitch patterns and designs without concern to the size
of the
spaces formed between the design pattern stitch seams where loose down
feathers
could be unstable or the complexity of the stitch patterns.
SUMMARY OF THE INVENTION
(0009) It is a feature of the present invention to provide a duvet cover which
substantially overcomes the above mentioned disadvantages of prior art duvet
covers and provides the above mentioned needs.
(0010) It is another feature of the present invention to provide a duvet cover
comprised of a pouch having internal attachments for removably securing
therein a
down insulating sheet which can be removed for washing the pouch thereby
prolonging the useful life of the down duvet cover
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(0011) Another feature of the present invention is to provide a duvet cover
having
all sorts of stitched design pattern wherein the propagation of down feathers
in
irregular pockets formed by the stitch seam patterns is not an issue.
(0012) A further feature of the present invention is to provide a duvet cover
wherein
pockets are formed to accommodate down feather sheets having different
insulation
factors.
(0013) A still further feature of the present invention is to provide a duvet
cover having
a down feather sheet secured inside the duvet cover and which can be disposed
in a
deployed or stored position.
(0014) A further feature of the present invention is to provide a duvet cover
wherein
the insulating factor thereof can be modified in whole or in part thereof.
(0015) According to the above features, from a broad aspect, the present
invention
provides a duvet cover which is comprised of a base sheet and a top sheet
interconnected together by stitched seams. A down feather sheet is retained
between
the base sheet and the top sheet. The down feather sheet has a substantially
constant
density of down feathers with the down feathers being retained captive by a
binder.
DESCRIPTION OF THE DRAWINGS
(0016) A preferred embodiment of the present invention will now be described
with
reference to the accompanying drawings in which:
(0017) Figure I is a perspective view of a duvet cover constructed in
accordance with
the present invention and wherein a decorative stitched design pattern is
formed in a
section of the duvet cover;
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(0018) Figure 2A is a cross-section view of a down feather sheet comprised of
down
feathers held together by binder fibers and adhered on a backing sheet;
(0019) Figure 2B is a cross-section view, similar to Figure 2A, but wherein
the down
feathers are held between opposed sheets;
(0020) Figure 3 is a plan view of a duvet cover wherein a down feather sheet
is held
captive between the base and top sheets of the duvet and a peripheral stitch
seam;
(0021) Figure 4A is a plan view of a duvet cover constructed in accordance
with the
prior art;
(0022) Figure 4B is a partial cross-section view of prior art Figure 4A
showing the
distribution of down feathers in the pockets;
(0023) Figure 5A is a plan view of a duvet cover having large transverse
pockets to
retains down feather sheets having different thermal insulation factors;
(0024) Figure 5B is a cross-section view, not to scale, of Figure 5A;
(0025) Figure 5C is a fragmented perspective view illustrating a stitched
design pattern
comprised of compressed stitched areas of different size and stitch line
spacing;
(0026) Figure 6A is a plan view of a duvet cover which is segmented into two
half
sections with the sections provided with a down feather sheet having different
thermal insulation factors and wherein an irregular stitched design pattern is
formed
in the top sheet of the sections;
(0027) Figure 6B is a cross-section view, not to scale, of Figure 6A;
(0028) Figure 7 is a fragmented perspective view of a duvet cover wherein the
down
feather sheet is rolled to a bottom of the duvet cover, such as to remove the
insulation factor of for ease of storage of the duvet cover;
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(0029) Figure 8 is a fragmented cross-sectional view illustrating the rolled-
up down
feather sheet held captive in a pouch formed along the bottom edge inside the
duvet
cover;
(0030) Figure 9 is a plan view of the duvet cover formed of two independent
longitudinal sections with each section formed in three transverse sections
each having
a double layer down feather sheet with the top layer being adapted to be
rolled upn
itself along a side edge of the duvet cover;
(0031) Figure 10 is a cross-sectional side view of the double layer down
feather sheet;
(0032) Figure 11 is a plan view of a duvet cover with a single double down
feather
sheet with the top down layer rolled to a side and retain in a manner as shown
in Figure
12;
(0033) Figure 12 is an enlarged fragmented cross-sectional view illustrating
the top
layer of the down sheet rolled on itself and retained by a holding flap;
(0034) Figure 13 is a perspective view, partly fragmented, illustrating
another
embodiment of the duvet cover and wherein it is comprised of a pouch having
attachments inside the pouch to removably retain therein a down insulating
sheet;
(0035) Figure 14 is a perspective view of the down insulating sheet adapted to
be
removable secured inside the pouch illustrated in Figure 13;
(0036) Figure 15 is a fragmented cross-section view of the down insulating
sheet
showing the securement of an attachment tab;
(0037) Figure 16 is an exploded fragmented cross-section view showing a tab of
the
down insulating sheet and a tab of the pouch being interconnected together by
means
of a button closure attachment,
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(0038) Figure 17 is a fragmented cross-section view showing a tab wherein the
attachment is provided by Velcro connectors, and
(0039) Figures 18A and 188 are end cross-section views illustrating a duvet
cover
comprised of a pouch in which two down insulation sheets are removably
attached one
on top of the other to modify the thermal insulation factor of the duvet cover
and
wherein one of the down insulation sheet may be smaller to suit the insulation
need in
a section only of the duvet cover
DESCRIPTION OF THE PREFERRED EMBODIMENT
(0040) Referring now to the drawings, and more particularly to Figures 1 to 3,
there is
shown a duvet cover 10 constructed in accordance with the present invention
and
disposed on a bed 11. The duvet cover 10 is formed by a base sheet 12 and a
top sheet
13 and a down feather sheet 14 disposed there between and interconnected
together
by stitched seams 15 or 16 or both. As shown in Figure 3, stitched seams 15
are formed
along the peripheral edges 16 of the duvet cover 10 to interconnect the base
sheet 12
and the top sheet 13 and which forms a pocket in which the down feather sheet
14 is
immovably trapped there between or sewn captive along one or more of the
stitched
seams 15. As shown in Figure 1 the down feather sheet 14, trapped between the
base
sheet 12 and the top sheet 13, is additionally secured by irregularly disposed
design
pattern stitched seams 16 to give an esthetically pleasing appearance to the
duvet
cover without concern to the large areas or pockets, such as areas 17, formed
between
stitch seams 16 spaced far apart as the down is held captive in the down
feather sheet
14 and does not propagate. The stitch seams 16 extend through the top sheet
13, the
down feather sheet 14 and the base sheet 12. Accordingly, the down feathers
are not
displaced when the duvet cover is manipulated during use. Also, the down
feather
sheet 14 provides a duvet cover with substantially uniform thermal insulating
density
throughout as well as uniform thickness.
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(0041) With reference to Figures 2A and 2B, the down feather sheet 14 is
comprised of
loose down feathers 18 mixed with a binder herein polyethylene fibers 19 or a
powder
adhesive binder and deposited on a support backing sheet 20 where it is caused
to bind
by the application of heat to form a homogeneous down feather sheet. Figure 2B
shows
another embodiment of the down feather sheet where the down is trapped and
bound
together and between opposed cover sheets 20 and 20'. The down feather sheet
14
may also be formed as disclosed in my above mentioned US Patent 6,025,041
where
the down feathers are bound together to form a homogeneous sheet without the
use
of support fiber sheets wherein the down sheet is of very light weight.
(0042) As shown in Figure 3, a slit opening 21 may be formed adjacent an edge
of the
duvet cover, herein the top edge to remove the down feather sheet 14 when
washing
the duvet cover. A fabric slit cover flap 22 is formed by an over-turned edge
portion of
the base sheet 12 or the flap may be formed by a different fabric piece sewn
on a top
edge section of the duvet cover to conceal the slit.
(0043) Figures 4A and 4B illustrate some of the above mentioned prior art
quilt pattern
stitch seam designs formed in duvet cover to maintain the loose down feathers
between the base sheet 25 and the top sheet 26. As shown in Figure 4A, the
quilt
pattern stitch seams 24 produces small square pockets 27 into which down is
held
captive. However, the close spacing of the stitch seams makes it impossible to
achieve a
high loft in the down feathers trapped in these small pockets 27 and therefore
limiting
the insulation factor of the down in the duvet cover. As shown in Figure 4B,
when larger
pockets 27 are formed by spacing the stitch seam lines 24 further apart, the
loose down
feathers 28 in the larger pockets 27 are unstable, and as herein shown the
down
propagates unevenly in these large pockets to form down clusters 29 where the
insulation factor is high, and areas 30 where there is very little or no down
and wherein
the insulation factor is very low. This creates a duvet cover with cold spots
created by
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irregular distribution of the down and accordingly irregular thermal
insulation. These
prior art disadvantages are obviated by the duvet cover 10 manufactured
according to
the present invention.
(0044) It is also desirable to also produce a duvet cover wherein a specific
section or
sections of the duvet cover has a different thermal insulating factor to form
areas which
are cooler on specific sections of the body of a user person. This is
achievable with the
present invention by different duvet designs formed by pattern stitch seams.
Some of
such designs are illustrated by Figures 5A to 5C. As shown in Figures 5A and
5B, the
duvet cover 10' is formed with three large transverse pocket sections 30, 30'
and 30" in
which there is retained a down feather sheet, with one or all of the sheets
having a
different thermal insulating factors or density. In the embodiment
illustrated, the
pocket section 30' has an insulating factor inferior to the other two pocket
sections 30
and 30" to provide less insulation or warmth in the lower torso section of a
person's
body which is favorable to a person's health when asleep. The pocket sections
are
defined by transverse seam lines 31 extending across the duvet cover 10'.
Slits 32 may
be formed at the end of each pocket sections for insertion and removal of the
down
feather sheets. Each slit 32 is concealed by a flap 33 formed as previously
described.
(0045) Figures 6A and 6B illustrate a further duvet cover 10" wherein the
duvet cover
is sectioned longitudinally by a central stitch seam 34 to form two half
pocket sections
35 and 35' to receive therein a down feather sheet having different thermal
insulating
factors wherein a person sleeping on one side of the bed receives less warmth
from the
duvet cover 10" than the person sleeping on the other side to suit the desire
of the user
persons. Again the down feather sheet is inserted and removed from these two
sections through associated slits 36 and 36' formed along an edge of the duvet
cover
and concealed by respective flaps 37 and 37'. If the down feather sheet is
meant to be a
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fixed and non-removable part of the duvet cover 10", design stitch seams 38
may be
formed in the duvet cover.
(0046) Figure 5C illustrates a still further embodiment of the duvet cover of
Figure 5A,
wherein the sections 30, 30' and 30" do not contain a removable down feather
sheet
but a permanent down feather sheet and wherein the loft of the down feathers
in their
sections is modified by applying design stitch seam patterns formed by
stitching. As
shown the central transverse section 30' has a design pattern throughout with
design
portions in the pattern having close stitch lines, such as portion 40, to
compress the
down feathers in that section thereby reducing the loft of the down and the
air trapped
therein to provide down compressed zones of less thermal insulating
efficiency. Other
design portions are formed as small square portions 41 wherein the down is
less
compressed than in the portion 40 but more compressed than in the adjacent
section
30 whereby to form a band or section 30' having an overall reduced thermal
insulation
efficiency than the adjacent sections 30 and 30" to achieve the same result as
the
embodiment illustrated in Figure 5A while providing an esthetic patch design
feature in
a large band extending across the duvet cover 10'. Because the down feathers
are not
loosely retained between the base sheet 12 and the top sheet 13 all sorts of
stitch
designs can be made without the concern of forming cold spots in the duvet
cover due
to loose down insulation.
(0047) With reference now to Figures 7 and 8 there is shown another embodiment
of
the duvet cover 10 of a type such as illustrated in Figure 3 wherein the down
feather
sheet 14 has a bottom edge section 14' held captive by the peripheral seam 15'
formed
in the lower edge of the duvet cover. The slit opening 21 provides access to
the down
feather sheet 14 to permit the down feather sheet to be rolled-up between the
base
sheet 12 and the top sheet 13 and stored in the bottom end of the duvet cover
when
not required during warmer weather periods. Still further a storage pouch 45
may be
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formed and attached in the lower peripheral seam 15' to retained the down
feather
sheet roll captive therein. The pouch can be held closed by a zipper fastener
or Velcro
(Registered Trademark) fastener 46 as herein illustrated. The down feather
sheet is
made easily accessible by turning the base sheet and top sheet inside-out
through the
slit 21.
(0048) Referring now to Figures 9 to 12 there is illustrated another
embodiment of the
present invention wherein the duvet cover 10" is a two-sided duvet cover, a
first side
50 and an adjacent second side 51, such as for use on a king size bed. Each
side 50 and
51 is divided into three transverse sections, 50', 50" and 50" for the first
side and 51',
51 "and 51" for the adjacent section 51. In each of these sections the is
secured a
double layer down feather sheet 52, as illustrated in Figure 10.
(0049) The bottom layer 53 of the double layer down feather sheet is secured
to the
base sheet 12 of the duvet cover adjacent a central longitudinal seam 56 by a
snap
attachment 55 or other suitable fastener or attachment The top layer 54 of the
double
layer down feather sheet 52 is detachably secured to the bottom layer 53 above
the
attachment 55 also by a snap attachment 56 or other suitable connection. Each
down
sheet layer 53 and 54 may have, for example, 50 grams/square meter of down
feathers
from goose or duck. Accordingly, the double layer sheet when folded provides
insulation in the order of 100 grams/square meter. If the top layer 54 is
rolled upon
itself along the edge of the duvet cover the insulating factor in any of the
transverse
sections can be reduced by half. Accordingly, the user person can adapt its
side of the
duvet cover for its personal comfort.
(0050) As shown in Figure 11 the top layer 54 has been rolled-up in a tight
roll 60
along the edge 61 of the duvet cover and is retained in that position by one
or more
retaining flaps 57 sewn to the inside face of the top sheet 13 of the duvet
cover 10". A
Velcro (registered trademark) connector 58 is secured to the retaining flap 57
and to
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another like matting connector 59 secured to a predetermined location on the
bottom
down feather sheet 53. Accordingly, the roll 60 is retained firmly in place.
Every one of
the transverse sections can be adjusted to suit the preference of each user
person.
(0051) Figure 12 shows a duvet cover 10 having a double layer down feather
sheet
which can form a roll 65 of its top layer for storage along a side edge of the
duvet
cover.
(0052) It is conceivable that the double layer down feather sheet can also be
used in
articles of apparel where the top sheet can be rolled to a concealing location
and held
in a pouch form with the article of apparel. Still, other applications of the
double layer
down feather sheet are conceivable.
(0053) With reference now to Figures 13 to 17 there will be described another
embodiment of the duvet cover wherein it is formed by a pouch 70, herein shown
of
rectangular shape and having an opening 71 along a longitudinal edge 72
thereof to
receive therein a down insulating sheet 73, as shown in Figure 14. The opening
71 has a
closure, such as a zipper 76 or buttons or other suitable closures. Anchoring
elements
or attachments 74 in the form of tabs are provided at convenient locations
inside the
pouch 70 and secured along the inner opposed parallel peripheral edges 75 of
the
pouch. As herein shown, these attachments 74 are disposed in the corners of
the
pouch and about mid-way along the opposed parallel side edges 72 of the pouch.
Likewise, the down insulating sheet 73 is also of rectangular shape and
dimensioned for
close fit inside the pouch and also provided with attachments 77 disposed
along its
opposed parallel edges at complimentary locations to the tabs 74 of the pouch.
(0054) To the tabs 74 and 77 there is secured complimentary connectors, and
has
herein illustrated in Figures 13 and 14, in the form of buttons 78 and button
slots 79. In
order to insert and secure the down insulating sheet 73 inside the pouch 70,
the pouch
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is pulled out through the opening 71 exposing the tabs 74 along the rear side
edge 72'
and attaching the tabs 77' along one of the side edges of the down insulating
sheet
thereto by the use of the buttons 78. The tabs at the end edges 72" can then
be
attached followed by the tabs at the edge 72 adjacent the opening. The tabs 74
and 77
may not be necessary to retain the down insulating sheet taunt inside the
pouch
depending on the size of the duvet cover. More attachment tabs may be provided
if
necessary.
(0055) The insulating down sheet 73 herein shown is comprised of a uniform
flat down
material layer 80 as shown in Figure 15, which is mixed with one or more
binders 81 in
the form of binding fibers and glue particles mixed together and held captive
between
opposed fabric sheets 82 and 83 by the binders mixed with the down. Such down
insulating fabric sheets are described in my US Patents No.6,025,041 and
9,380,893.
Such a down insulating sheet is of constant thickness and has a constant
thermal
insulating factor for the reason that the down in the insulating sheet does
not shift. By
removably securing the down insulating sheet 73 in a pouch 70, the pouch can
be
washed without having to wash the down insulating sheet which is removed. This
assures that the down in the insulating sheet is not affected by washing and
the
tumbling and stretching action of a drying machine which can damage the
insulating
sheet causing clumping or tears therein thereby destroying the constant
insulating
factor of the duvet cover. Also, seeing that the down insulating sheet is of
constant and
uniform shape throughout, the duvet cover pouch has a uniform flat shape
without the
need, as in the prior art, of having the make quilt stitching throughout the
duvet cover
to stabilize the loose insulation therein, whether down, feathers, artificial
insulation,
etc.
(0056) With reference to Figures 16 and 17, there is shown different types of
connectors secured to the tabs. As shown in Figure 16 the tab 77 of the of the
down
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insulating sheet 73 is secured along the edge of the sheet by stitches 85 and
a button
fastener 86 is secured to the tab 77 for snap connection with a complimentary
cup
fastener 87, secured to the tab 74 of the pouch 70. Figure 17 shows an
alternative
connection means in the form of Velcro (registered trademark) fasteners.
Instead of
Velcro strip material, it is also conceivable that the fasteners may consist
of magnetic
tabs, or any other suitable fastening means.
(0057) Referring now to Figures 18A, there is shown a further modification of
the
duvet cover and namely the possibility of modifying the thermal insulating
factor of the
duvet cover. This can be accomplished by inserting into the pouch a further
down
insulation sheet 73', as shown in Figure 18A, which has a different insulation
factor, for
example 60 grams/sq. meter over a slightly thicker insulation sheet 73 of 120
grams/sq.
meter. The second sheet 73' is also provided with attachment tabs 77 which are
secured to the pouch tabs 74 of the tabs of the other down insulation sheet
73.
(0058) Figure 18B illustrates a further embodiment in that a smaller or
sectional down
insulation sheet 73" is secured inside the pouch and extends in a specific
portion of the
pouch to suit the need of a person sleeping on one side of a bed with the
duvet cover
on its side having a higher thermal insulating factor that the other side.
Also, a
sectional down insulation sheet may be attached across a lower portion of the
pouch
70 to provide more warmth in the feet area of the duvet cover.
(0059) It is within the ambit of the present invention to cover various
obvious
modifications of the embodiments and examples described herein provided
such modifications fall within the scope of the appended claims.
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