U.S. patent application number 12/838170 was filed with the patent office on 2011-01-27 for surface cleaning appliance.
This patent application is currently assigned to DYSON TECHNOLOGY LIMITED. Invention is credited to Edward Jonathan CHUDLEIGH.
Application Number | 20110016657 12/838170 |
Document ID | / |
Family ID | 41058441 |
Filed Date | 2011-01-27 |
United States Patent
Application |
20110016657 |
Kind Code |
A1 |
CHUDLEIGH; Edward Jonathan |
January 27, 2011 |
SURFACE CLEANING APPLIANCE
Abstract
A surface cleaning appliance incorporating a flexible hose. The
hose is a stretch hose, which is extendable lengthways from a
retracted length to an extended length under a tensile force
applied to the hose, the extended length being at least 25% longer
than the retracted length. A length of the hose has a hose wall
formed at least in part by a layer of fabric which is sealed to
form an impermeable barrier for the fluid carried by the hose, and
which therefore provides a layer which is both impermeable and has
a high resistance to cyclic fatigue.
Inventors: |
CHUDLEIGH; Edward Jonathan;
(Malmesbury, GB) |
Correspondence
Address: |
MORRISON & FOERSTER LLP
1650 TYSONS BOULEVARD, SUITE 400
MCLEAN
VA
22102
US
|
Assignee: |
DYSON TECHNOLOGY LIMITED
Malmesbury
GB
|
Family ID: |
41058441 |
Appl. No.: |
12/838170 |
Filed: |
July 16, 2010 |
Current U.S.
Class: |
15/327.1 |
Current CPC
Class: |
A47L 9/248 20130101;
B29L 2023/18 20130101; B29K 2105/0809 20130101; F16L 11/112
20130101; F16L 11/115 20130101; B29C 53/582 20130101 |
Class at
Publication: |
15/327.1 |
International
Class: |
A47L 5/00 20060101
A47L005/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 23, 2009 |
GB |
0912838.0 |
Claims
1. A surface cleaning appliance comprising: a flexible hose, a
length of the hose being extendable lengthways from a retracted
length to an extended length under a tensile force applied to the
hose, the extended length being at least 25% longer than the
retracted length, wherein said length of the hose has an extendable
hose wall formed at least in part by one or more layers of fabric,
at least one layer of fabric being sealed to form an impermeable
barrier to fluid carried by the hose.
2. A surface cleaning appliance according to claim 1, wherein the
hose wall is a fabric hose-wall consisting of one or more layers of
fabric, at least one of the layers of fabric being sealed to form
an impermeable barrier to the fluid carried by the hose.
3. A surface cleaning appliance to claim 1, wherein one or more of
said layers of fabric is substantially inelastic and incorporates
sufficient slack for non-elastic, lengthways extension of the hose
wall from the retracted length to the extended length.
4. A surface cleaning appliance according to claim 3, wherein at
least some of the slack is provided by a series of corrugations or
folds in the fabric.
5. A surface cleaning appliance according to claim 1, wherein at
least one of the layers of fabric is woven, braided or knitted at
least in part from plastic filaments.
6. A surface cleaning appliance according to claim 1, wherein the
hose-wall incorporates at least one layer of ripstop fabric.
7. A surface cleaning appliance claim 1, wherein the hose-wall is
secured to one or more reinforcing frame elements arranged for
lengthways movement relative to one another in order to accommodate
extension of the hose wall from the retracted length to the
extended length.
8. A surface cleaning appliance according to claim 7, wherein the
frame elements are resiliently connected to one another for
providing a restoring force to return the hose wall from the
extended length to the retracted length.
9. A surface cleaning appliance according to claim 7, wherein one
or more of the frame elements is sandwiched radially in-between
layers or plies of fabric forming part of the hose wall.
10. A surface cleaning appliance according to claim 9, wherein said
layers or plies of fabric are bonded to one another, axially either
side of the respective frame element, to encapsulate the frame
element between the layers or plies of fabric.
11. A surface cleaning appliance according to claim 7, 8, 9 or 10,
wherein the fabric in the hose wall is arranged to form a multi-ply
or multi-layer overlap around the outside of one or more of the
frame elements.
12. A surface cleaning appliance according to claim 7, wherein the
hose wall comprises a layer consisting of a wound fabric tape.
13. A surface cleaning appliance according to claim 12, wherein one
or more of the frame elements is sandwiched radially in-between two
axially-overlapping passes of the wound fabric tape.
14. A surface cleaning appliance according to claim 12, wherein two
or more axially overlapping passes of the wound falbric tape form a
respective multi-ply overlap around the outside of one or more of
the frame elements.
15. A surface cleaning appliance according to claim 7, wherein the
frame elements are coils on a resilient helical supporting
member.
16. A surface cleaning appliance according to claim 1, wherein the
hose is provided on the appliance as part of a hose and wand
assembly.
Description
REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the priority from UK Application No.
0912838.0, filed Jul. 23, 2009, the entire contents of which are
incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates generally to surface cleaning
appliances having an extendable flexible hose, or so-called
"stretch" hose, possibly provided as part of a hose and wand
assembly for the appliance.
BACKGROUND OF THE INVENTION
[0003] Domestic vacuum cleaners, namely those vacuum cleaners which
are intended for domestic use, generally fall into two categories:
"cylinder" cleaners and "upright" cleaners.
[0004] In a typical cylinder cleaner a, shown in FIG. 1, a main
body b of the cleaner a is fluidly connected to a floor tool c via
a hose and wand assembly. The hose and wand assembly consists of a
relatively in-extendable, flexible hose d which is connected at one
end to a suction inlet on the main body b, and a rigid, hollow,
telescopic wand e which connects the opposite end of the flexible
hose d to the floor tool c. During normal operation of the cleaner
a, a user grasps the wand e manually to maneuver the floor tool c
across the floor, dragging the main body b behind with the
in-extendible, flexible hose d.
[0005] In a typical upright cleaner f, shown in FIG. 2a, a cleaner
head g is permanently attached to the main body h of the vacuum
cleaner and the user maneuvers the cleaner head g and the main body
h together across the floor using a handle i. Historically, only
cylinder cleaners were provided with a suction hose: upright
cleaners relied solely on the cleaner head permanently attached to
the main body of the cleaner. More recently, manufacturers have
started to provide upright vacuum cleaners with a hose and wand
assembly, in addition to the cleaner head, so that the upright
cleaner can optionally be operated in the manner of a cylinder
cleaner. FIG. 2b shows a particularly compact form of hose and wand
assembly, used generally on models from the Dyson range of upright
vacuum cleaners, in which a telescopic wand j is integrated with
the handle i and can be released from the main body h by operating
a catch. A so-called "stretch" hose k attaches the wand j to a
suction inlet (not shown) on the main body h; the stretch hose k is
stored on-board the main body h in a retracted position and can
then be manually extended, or "stretched", as desired following
release of the wand j (with the handle i) in order to increase the
useful reach of the wand j. A suitable floor tool l can be attached
to the suction inlet on the wand j, as desired.
[0006] Hoses for early models of cylinder cleaner were often
constructed using rubber, an example of which is described in UK
Patent No. GB836407. These rubber or rubber-based hoses were,
however, superseded relatively quickly by plastic suction hoses,
typically comprising a molded thermoplastic hose wall having a
series of corrugations to provide the requisite flexibility for the
hose, as appropriate. The use of plastic significantly reduces the
weight of the hose compared to a corresponding rubber or
rubber-based hose, and the molded plastic suction hose has become
the well-established industry norm for domestic vacuum cleaners,
whether in the form of a relatively in-extendible suction hose on a
cylinder cleaner or a stretch hose on modern upright cleaners.
[0007] Molded plastic hoses are also commonly used as a suction or
blow pipe in industrial (non-domestic) surface-cleaning appliances,
and are used in other fields in which it is likewise desirable to
provide a hose which is relatively lightweight and low-cost to
produce.
SUMMARY OF THE INVENTION
[0008] An object of the present invention is to seek to provide a
surface-cleaning appliance incorporating an improved stretch hose,
possibly as part of a hose and wand assembly for the appliance,
which offers an advantageous alternative to the conventional molded
plastic stretch hose commonly used on upright domestic vacuum
cleaners.
[0009] According to the present invention there is provided a
surface-cleaning appliance, preferably a domestic vacuum cleaning
appliance, comprising a flexible hose, a length of the hose being
extendable lengthways from a retracted length to an extended length
under a tensile force applied to the hose, the extended length
being at least 25% longer than the retracted length, wherein said
length of the hose has an extendable hose wall formed at least in
part by one or more layers of fabric, at least one layer of fabric
being sealed to form an impermeable barrier for the fluid carried
by the hose.
[0010] The present invention is concerned with stretch hoses, which
have an extended length which is significantly longer than their
retracted length in the context of the use of the hose. Thus, the
extended length will be at least 25% longer than the retracted
length (e.g. an extended length of 125 cm versus a retracted length
of 100 cm), but may typically be in the range of 2 to 6 times the
retracted length of the hose, and possibly up to 20 times the
retracted length of the hose.
[0011] The hose may be extendable in response to a manual tensile
force, for example a force exerted manually by the user of a vacuum
cleaner.
[0012] The use of a fabric stretch hose in particular breaks with
the long-established industry norm for domestic vacuum cleaning
appliances, which have almost exclusively continued to rely on
conventional molded plastic hoses. In such conventional molded
plastic stretch hoses, it has been found that the hose wall can
suffer from cyclic fatigue caused by repeated extension and
retraction of the hose, increasing the risk of the hose splitting.
The fatigue life of the hose can be increased by increasing the
thickness of the hose-wall, but this often carries with it a weight
penalty, and may also critically reduce the flexibility and/or
extensibility of the hose in certain applications. The use of a
fluid-tight fabric layer in accordance with the present invention
is aimed at providing a layer which is both impermeable, highly
flexible and has a relatively high tolerance to cyclic fatigue,
thus advantageously improving the useful life of the hose as
compared to a comparable, conventional plastic hose, without
critically affecting the flexibility or weight of the hose.
[0013] The hose wall may be a fabric hose wall i.e. constructed
solely from one or more layers of fabric. This sort of fabric
construction offers a lightweight, highly flexible alternative to a
conventional molded plastic hose offering comparable fatigue
life.
[0014] One or more of the layers of fabric may be substantially
inelastic, and may incorporate sufficient slack for non-elastic
lengthways extension of the hose wall from the retracted length to
the extended length. At least some of the slack may conveniently be
provided by a series of corrugations or folds in the fabric.
[0015] The fabric hose-wall may comprise woven, braided or knitted
plastic or plastic coated filaments.
[0016] The hose wall may incorporate at least one layer of ripstop
fabric, being a fabric which is interwoven with a pattern of
reinforcing yarns, typically a cross-hatch pattern, and which
consequently exhibits high resistance to the formation and spread
of tears and runs in the fabric. The ripstop fabric may be ripstop
nylon or ripstop polyester, but the invention is not limited to any
particular fabric. The reinforcing yarns in the ripstop fabric do
not necessarily need to be the same material as the bulk
fabric.
[0017] The layer of ripstop fabric provides a tear and puncture
resistance layer in the hose-wall. The layer of ripstop fabric
itself may be relatively thin, possibly less than 0.1 mm in the
case of a hose for a domestic vacuum cleaning appliance, and
therefore does not add any significant weight to the hose. The
ripstop fabric is also highly flexible.
[0018] The hose-wall may be supported on one or more frame
elements, providing increased crush strength and stiffness for the
hose. This helps to maintain an open flow passage through the
hose.
[0019] The frame elements are arranged for lengthways movement
relative to one another to accommodate extension of the fabric wall
from the retracted length to the extended length. The frame
elements may be resiliently connected to one another for providing
a restoring force to return the fabric wall from the extended
length to the retracted length.
[0020] One or more of the frame elements may be sandwiched radially
in-between either two separate layers of fabric in the hose wall
or, alternatively, two plies of fabric (which may be formed by
doubling over a single layer of fabric), so that the frame
element(s) is (are) not exposed on the outside of the hose
wall.
[0021] During use of the hose, frictional wear of the fabric may
occur, principally along the contact interface between the frame
elements and the fabric, which may eventually lead to breach of the
hose wall (and consequent loss of suction in the case of a suction
hose for a surface cleaning appliance). The provision of two
sandwiching layers or plies of fabric reduces the effect of this
frictional wear by increasing the effective thickness of the hose
wall. At the same time, providing the inner sandwiching layer (or
ply) on the inside of the frame element has the advantage that this
inner sandwiching layer is not exposed to the relatively high
levels of frictional wear which typically occur around the outside
of the frame elements.
[0022] The layers or plies of fabric may be bonded to one another,
axially either side of the respective frame element, to encapsulate
the frame element between the layers or plies of fabric, thus
conveniently retaining the frame elements in their predetermined
positions. The fabric making up the hose wall may additionally or
alternatively be arranged to form a multi-ply or multi-layer
overlap around the outside of one or more of the frame elements,
further improving the external wear resistance of the hose.
[0023] It has also been found that coating the frame elements with
a relatively compliant or low-friction material (i.e. compliant or
low-friction relative to the material making up the frame elements)
has a significant effect on the wear resistance of the hose. For
example, if the frame elements are steel, the wear resistance of
the hose can be improved significantly by coating the frame
elements with a plastic e.g. polyurethane (PU), thermoplastic
polyurethane (TPU) or polytetrafluoroethylene (PTFE)
[0024] The hose wall may comprise a wound fabric tape. In a
particular embodiment, the hose wall comprises a wound fabric tape,
and one or more of the frame elements are sandwiched radially
in-between two axially-overlapping passes of the wound fabric tape.
The respective overlapping passes of the fabric may be bonded to
one another, axially either side of the corresponding frame element
in order to encapsulate the frame element. Additionally or
alternatively, the wound fabric tape may be arranged so that two or
more axially overlapping passes if the fabric tape form a
respective multi-ply overlap around the outside of one or more of
the frame elements. These winding arrangements are considered to be
particularly effective for reducing the effects of frictional wear;
this is particularly the case during use on a typical domestic
vacuum cleaning appliance, where preliminary tests indicate that
winding a ripstop fabric tape in the manner described above can
dramatically increase the life of the hose compared to a
conventional molded plastic hose. The winding arrangements
described above also present a relatively smooth internal surface
to the hose, tending to limit the thickness of the boundary layer
flow through the hose.
[0025] The hose-wall may be bonded to the frame elements, for
example using an adhesive. If the frame elements are formed from an
electrically conductive material, the adhesive may be cured by
resistance-heating the frame elements.
[0026] The frame elements may be coils on a helical supporting
member, which may be a helical metal wire. The fabric may
conveniently be wrapped around the helical supporting member using
any suitable wrapping arrangement.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Embodiments of the invention will now be described with
reference to the accompanying drawings, in which:
[0028] FIG. 1 is a schematic, perspective view of a conventional
cylinder cleaner incorporating a flexible suction hose;
[0029] FIGS. 2a and 2b are schematic, side views of a conventional
upright cleaner incorporating a flexible suction hose;
[0030] FIG. 3 is a schematic perspective view of a retracted length
of flexible, extendable hose in accordance with the present
invention;
[0031] FIG. 4a is a sectional view of the hose shown in FIG. 3,
taken along the line A-A;
[0032] FIG. 4b is a sectional view corresponding to FIG. 4a, but
showing the hose in an extended configuration;
[0033] FIG. 5 is a sectional view showing an alternative form of
hose in accordance with the present invention, in which the hose
wall has a multi-layer fabric construction;
[0034] FIG. 6 is a sectional view showing an alternative form of
hose, in which the hose wall is constructed from wound fabric
tape;
[0035] FIG. 7 is a sectional view through part of the fabric hose
wall shown in FIG. 6;
[0036] FIG. 8 is a sectional view through a length of hose,
illustrating an alternative hose wall configuration utilizing a
wound fabric tape; and
[0037] FIG. 9 is a sectional view through a length of hose,
illustrating a further alternative hose wall configuration
utilizing a wound fabric tape.
DETAILED DESCRIPTION OF THE INVENTION
[0038] Referring first of all to FIG. 3, an extendable length of
hose 1 comprises a hose-wall 2 which is supported on a helical
supporting member 3.
[0039] The helical supporting member 3 is resiliently extendable
lengthways (along the axis x in FIG. 3) from a retracted length
L.sub.r, shown in FIG. 4a, to an extended length L.sub.e, shown in
FIG. 4b.
[0040] The hose wall 2 consists of a single layer of substantially
inelastic fabric, which is sealed to prevent escape of fluid
through the hose-wall 2. The hose-wall 2 thus represents an
impermeable barrier for containing a fluid under transport,
indicated by the flow arrow A through the hose 1 in FIG. 4b. The
fabric may be ripstop fabric, for example ripstop Nylon or
polyester.
[0041] The fabric hose-wall 2 is secured to the helical supporting
member 3, but is provided with sufficient axial slack to
accommodate substantially non-elastic lengthways extension from the
retracted length L.sub.r to the extended length L.sub.e. Thus, with
the helical supporting member 3 at its retracted length L.sub.r,
the fabric hose-wall forms a series of corrugations in between the
successive coils of the helical supporting member 3, which
corrugations are then taken up during lengthways extension of the
hose-wall to the extended length L.sub.e, as illustrated in FIG.
4b. The fabric hose-wall 2 may be arranged to fold along
pre-determined lines, so that the hose-wall tends to form a series
of tighter, predefined folds between successive coils of the
helical supporting member 3 rather than the more `loose`
corrugations shown in FIG. 4a.
[0042] The fabric hose wall 2 may be sealed by impregnating,
spray-coating or dip-coating the fabric with a sealant such as
polyurethane (PU), a thermoplastic polyurethane (TPU) or polyvinyl
chloride (PVC), or in general by using any suitable plastification
process.
[0043] The fabric may be sheet fabric, produced for example by
weaving, braiding or knitting, in which case the sheet fabric may
be wrapped around the outside of the helical supporting member 3 to
form the tubular hose-wall 2. The fabric may be wrapped tightly to
form a compression-fit on the helical supporting member 3 (but
still providing the necessary axial slack for lengthways extension
of the hose wall 2). The hose-wall 2 may be securely bonded to the
helical supporting member 3, for example using a heat-curable
adhesive such as a suitable solvent-based or epoxy adhesive, which
may be applied to one or both of the hose-wall 2 and the helical
supporting member 3, possibly as a pre-coating prior to wrapping of
the fabric. If the helical supporting member 3 is in the form of a
coil of metal wire, the adhesive may conveniently be heat-cured by
resistance-heating the wire using a suitable electric current.
[0044] In an alternative arrangement, the ripstop fabric is
produced as a seamless, tubular fabric, produced for example by
tubular-weaving, tubular-braiding or tubular-knitting, and the
hose-wall 2 is formed by rolling the fabric tube lengthways onto
the helical supporting member 3. A pre-form fabric tube may also be
produced from sheet fabric by initially wrapping the fabric around
a cylindrical mandrel and bonding the sheet fabric along a seam to
form the tube. Again, the relative diameter of the hose-wall 2 may
be controlled to form a slight compression-fit on the helical
supporting member 3 and the hose-wall may be securely bonded to the
helical supporting member 3 using a heat-curable adhesive.
[0045] In FIGS. 4a and 4b, successive coils 3a, 3b, 3c of the
helical supporting member 3 constitute a continuous set of frame
elements for supporting the hose-wall 2. FIG. 5 shows an
alternative arrangement, in which a length of stretch hose 10 has a
hose-wall 20 supported on a non-continuous set of frame elements,
in the form of individual frame rings 30 which are bonded
separately to the inside of the hose-wall 20.
[0046] The stretch hose 10 is shown at an extended length Le in
FIG. 5, with the hose-wall 20 being pulled taut between the frame
rings 30, under the tensile force T. The frame rings 30 are
separate from one another and do not therefore provide any
restoring force for returning the hose to a retracted length. A
suitable restoring force may nevertheless be provided, if desired,
by using an elastic fabric in the hose wall 2. Upon return of the
length of hose 10 to its retracted length, the hose wall 20 assumes
a corrugated profile, similar to the profile of the hose wall 2
shown in FIG. 4a.
[0047] The hose-wall 20 has a multi-layer fabric wall construction,
consisting of an intermediate layer of fabric 20a sandwiched
between an inner and outer layer of fabric 20b, 20c. The layers of
fabric 20a, 20b, 20c do not need to consist of the same fabric; for
example, layer 20a may be a ripstop fabric, whereas layers 20b and
20c may be some other fabric intended to impart a desirable
property to the hose wall e.g. chemical or fire resistance. At
least one of the layers 20a, 20b, 20c is sealed to prevent escape
of fluid through the hose-wall 20.
[0048] Each of the layers of fabric 20a, 20b, 20c may be formed
from either sheet fabric or tubular fabric. For example, the fabric
layer 20a may be formed as a seamless, tubular fabric, and the
layers 20b and 20c may be formed from sheet fabric which is
successively wrapped around the inner, tubular fabric layer 20a.
The fabric layers 20a, 20b, 20c may be bonded to one another using
a heat-curable adhesive, which may be cured by resistance-heating
each frame ring 30 separately, possibly using some sort of
switching circuit. Alternatively, where surface-sealing of the
layer or layers of fabric, 20a, 20b, 20c is by impregnation, the
impregnating sealant may also be used effectively to bond the
fabric layers 20a, 20b, 20c.
[0049] FIG. 6 is a sectional view illustrating a multi-layer fabric
hose wall formed using two ripstop fabric tapes 200 and 201.
[0050] Each of the fabric tapes 200 and 201 is wound around to form
a respective fabric layer along the length of the helical
supporting member 3. In the case of the fabric tape 200, this forms
a respective fabric layer 210 on the outside of the helical
supporting member 3 consisting of a series of axially-overlapping
passes of fabric 200a, 200b, 200c etc. In the case of fabric tape
201, this forms a respective fabric layer 211 on the inside of the
helical supporting member 3 consisting of a series of overlapping
passes of fabric 201a, 201b, 201c etc.
[0051] The coils 3a, 3b, 3c etc. of the helical supporting member 3
are sandwiched radially in-between the two fabric layers 210, 211.
For example, the coil 3a is sandwiched between the passes 200a,
201a, the coil 3b is sandwiched between the passes 200b, 201b and
so on. In addition, overlapping passes of the fabric tape 200 form
a series of double-ply overlaps on the outside of the coils 3a, 3b,
3c etc. For example, the overlapping passes 200a and 200b form a
double-ply overlap on the outside of the coil 3a, the overlapping
passes 200b and 200c form a double-ply overlap on the outside of
the coil 3b and so on. In the arrangement shown in FIG. 6,
overlapping passes of the fabric tape 201 additionally form
corresponding double-ply overlaps on the inside of the coils 3a,
3b, 3c, but the double-ply-overlaps on the outside of the helical
supporting member 3 are considered to be particularly advantageous
for a suction hose on a domestic cleaning appliance, because they
are associated with regions of the hose-wall that are typically
subject to relatively high frictional wear.
[0052] The fabric tapes 200, 201 may be pre-wound on a mandrel and
then fitted onto the helical supporting member 3 in similar manner
to a pre-form fabric tube, possibly following bonding of the
overlapping passes of fabric to consolidate the pre-wound
configuration of the fabric tape.
[0053] The overlapping passes 200a, 201a are bonded to one another
axially either side of the coil 3a, as indicated by the vertical
dotted lines in FIG. 7, in order to encapsulate the coil 3a between
the fabric tapes 200, 201. In addition, the passes 200a, 201a are
bonded respectively to the passes 200b, 201b.
[0054] The fabric tapes 200, 201 are wound around the helical
supporting member 3 with the helical supporting member stretched to
its extended length L.sub.e, shown in FIG. 6, under an applied
tensile force. Following winding of the fabric tapes 200, 201 the
applied tensile force is then removed, and the helical supporting
member returns to its retracted length, with the hose wall assuming
a generally corrugated profile, similar to the profile of the hose
wall 2 in FIG. 4a.
[0055] FIG. 6 illustrates one possible winding arrangement using
fabric tape, but other arrangements are possible. Thus, in FIG. 8,
a single ripstop fabric tape 203 is wound onto the helical
supporting member 3, along the direction x, with a trailing portion
of the fabric tape 203 running around the outside of the coils 3a,
3b, 3c and a leading portion of the fabric tape 203 running around
the inside of the coils 3a, 3b, 3c. In this case, each of the coils
3a, 3b, 3c is sandwiched radially in-between overlapping passes of
the single fabric tape 203, without the need for a second fabric
tape. For example, the coil 3b is sandwiched between overlapping
passes 203a and 203b, which may be bonded to one another axially
either side of the coil 3b in order to encapsulate the coil 3b in
position.
[0056] A single ripstop fabric tape may be wound additionally to
form a multi-ply overlap on the outside of a frame element. FIG. 9
illustrates one such "dual function" winding arrangement; the
arrangement shown in FIG. 9 is similar to the arrangement shown in
FIG. 8, but utilizes a relatively wide ripstop fabric tape 204
additionally to form a series of double-ply overlaps on the outside
of the coils 3a, 3b, 3c. In this case, the ripstop fabric tape 204
is arranged such that each of the coils 3a, 3b, 3c is sandwiched
radially in-between first and second overlapping passes of the
fabric tape 204, while the second overlapping pass additionally
overlaps a third pass of the fabric tape 204 to form a double-ply
layer overlap on the outside of the coil. For example, the coil 3a
is sandwiched between successive overlapping passes 204a and 204b,
while pass 204b additionally forms a double ply overlap with
successive overlapping pass 204c. The overlapping passes 204a and
204b may be bonded to one another axially either side of the coil
3a to encapsulate the coil in position. In addition, the
overlapping passes 204b and 204c may be bonded to one another in
the region of the respective double-ply overlap.
[0057] Although in the embodiments described, the frame elements
are located on the inside, or encapsulated within, the hose-wall,
the invention is not intended to be limited to such arrangements
and the frame elements may alternatively be provided on the outside
of the hose wall.
[0058] The invention concerns a surface-cleaning appliance,
preferably a domestic vacuum cleaning appliance. The hose may be
incorporated as part of a hose and wand assembly for the appliance,
and in any event may be fitted to a main body of the appliance
using conventional fittings. The main body of the appliance may in
particular be a conventional upright body on a domestic upright
cleaner, such as the main body h in FIGS. 2a and 2b.
[0059] Although in the embodiments described the hose incorporates
a fabric hose-wall i.e. a hose wall constructed entirely from one
or more layers of fabric, in its broadest sense the invention is
not limited to arrangements wherein the stretch hose has a fabric
hose-wall. The hose wall may, for example, additionally incorporate
an extruded or injection-molded plastic protective sheath or
lining. Nevertheless, it is believed that the use of an impermeable
fabric layer in the hose-wall will improve the resistance of the
hose wall to cyclic fatigue and thus improve the useful life of the
hose as compared to a conventional extruded or injection-molded
plastic stretch hose.
* * * * *