U.S. patent application number 13/997103 was filed with the patent office on 2013-12-19 for fan.
This patent application is currently assigned to Dyson Technology Limited. The applicant listed for this patent is Rodney James Brown, James Dyson, Neil Andrew Stewart. Invention is credited to Rodney James Brown, James Dyson, Neil Andrew Stewart.
Application Number | 20130336771 13/997103 |
Document ID | / |
Family ID | 43598944 |
Filed Date | 2013-12-19 |
United States Patent
Application |
20130336771 |
Kind Code |
A1 |
Dyson; James ; et
al. |
December 19, 2013 |
FAN
Abstract
A ceiling fan includes an annular nozzle having an inner wall,
an outer wall extending about the inner wall, an air inlet for
receiving an air flow, an air outlet for emitting the air flow, and
an interior passage located between the inner wall and the outer
wall for conveying the air flow to the air outlet. The inner wall
defines a bore through which air from outside the nozzle is drawn
by the air flow emitted from the air outlet. The fan includes a
support assembly for supporting the nozzle on a ceiling. The nozzle
is rotatable relative to the support assembly about a rotational
axis and between a first orientation in which the air flow is
directed away from the ceiling and a second orientation in which
the air flow is directed towards the ceiling.
Inventors: |
Dyson; James; (Malmesbury,
GB) ; Stewart; Neil Andrew; (Malmesbury, GB) ;
Brown; Rodney James; (Malmesbury, GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Dyson; James
Stewart; Neil Andrew
Brown; Rodney James |
Malmesbury
Malmesbury
Malmesbury |
|
GB
GB
GB |
|
|
Assignee: |
Dyson Technology Limited
Maimesbury
SN
|
Family ID: |
43598944 |
Appl. No.: |
13/997103 |
Filed: |
November 25, 2011 |
PCT Filed: |
November 25, 2011 |
PCT NO: |
PCT/GB2011/052328 |
371 Date: |
August 2, 2013 |
Current U.S.
Class: |
415/126 |
Current CPC
Class: |
F24F 7/007 20130101;
F24F 13/32 20130101; F24F 2221/16 20130101; F04F 5/46 20130101;
F04D 25/088 20130101; F04D 25/08 20130101; F04F 5/16 20130101; F04D
29/483 20130101 |
Class at
Publication: |
415/126 |
International
Class: |
F04D 29/48 20060101
F04D029/48 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 23, 2010 |
GB |
1021910.3 |
Claims
1. A ceiling fan comprising: an annular nozzle comprising an inner
wall, an outer wall extending about the inner wall, an air inlet,
at least one air outlet, and an interior passage located between
the inner wall and the outer wall for conveying an air flow to said
at least one air outlet, the inner wall defining a bore through
which air from outside the nozzle is drawn by the air flow emitted
from said at least one air outlet; and a support assembly for
supporting the nozzle on a ceiling; wherein the nozzle is rotatable
relative to the support assembly about a rotational axis and
between a first orientation in which the air flow is directed away
from the ceiling and a second orientation in which the air flow is
directed towards the ceiling.
2. The ceiling fan of claim 1, wherein the nozzle is inverted as it
is rotated between the first orientation and the second
orientation.
3. The ceiling fan of claim 1, wherein the rotational axis is
substantially orthogonal to an axis of the bore.
4. The ceiling fan of claim 1, comprising an air inlet section
housing a device for generating the air flow.
5. The ceiling fan of claim 4, wherein the device for generating
the air flow is located between the support assembly and the
annular nozzle.
6. The ceiling fan of claim 4, wherein the device for generating
the air flow is connected to the annular nozzle for rotation
therewith as the annular nozzle is rotated relative to the support
assembly between the first orientation and the second
orientation.
7. The ceiling fan of claim 1, wherein the support assembly
comprises an air passage disposed upstream of the at least one air
outlet.
8. The ceiling fan of claim 7, wherein the air passage has a
longitudinal axis, and wherein the rotational axis is substantially
co-planar with the longitudinal axis of the air passage.
9. The ceiling fan of claim 7, wherein the air passage is arranged
to convey an air flow to the annular nozzle.
10. The ceiling fan of claim 1, wherein the nozzle is pivotable
relative to at least part of the support assembly.
11. The ceiling fan of claim 10, wherein the nozzle is pivotable
relative to said at least part of the support assembly about a
pivot axis which is substantially orthogonal to the rotational axis
of the annular nozzle.
12. The ceiling fan of claim 10, wherein the nozzle is pivotable
relative to said at least part of the support assembly between a
raised position and a lowered position to allow the nozzle to be
rotated between the first orientation and the second
orientation.
13. The ceiling fan of claim 12, wherein the rotational axis is
substantially horizontal when the body is in the raised position
and the support assembly is connected to a substantially horizontal
ceiling.
14. The ceiling fan of claim 12, wherein the nozzle is pivotable
about an angle in the range from 5 to 45.degree. from the raised
position to the lowered position.
15. The ceiling fan of claim 12, wherein the nozzle is pivotable
about an angle in the range from 10 to 20.degree. from the raised
position to the lowered position.
16. The ceiling fan of claim 12, wherein the support assembly
houses a releasable locking mechanism for locking the nozzle in the
raised position.
17. The ceiling fan of claim 1, wherein the nozzle comprises an air
outlet section extending between the inner wall and the outer wall,
and the air outlet section comprising said at least one air
outlet.
18. The ceiling fan of claim 17, wherein the air outlet section
comprises an inner section connected to the inner wall, and an
outer section connected to the outer wall, and wherein at least
part of the inner section tapers away from the bore axis.
19. The ceiling fan of claim 18, wherein an angle of inclination of
said at least part of the inner section to the bore axis is between
0 and 45.degree..
20. The ceiling fan of claim 18, wherein said at least part of the
inner section has a shape which is substantially conical.
21. The ceiling fan of claim 18, wherein said at least one air
outlet is located between the inner section and the outer
section.
22. The ceiling fan of claim 18, wherein the outer section is
substantially orthogonal to an axis of the bore.
23. The ceiling fan of claim 1, wherein said at least one air
outlet extends about an axis of the bore.
24. The ceiling fan of claim 1, wherein said at least one air
outlet comprises a substantially annular air outlet.
Description
REFERENCE TO RELATED APPLICATIONS
[0001] This application is a national stage application under 35
USC 371 of International Application No. PCT/GB2011/052328, filed
Nov. 25, 2011, which claims the priority of United Kingdom
Application No. 1021910.3, filed Dec. 23, 2010, the entire contents
of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to a fan assembly for
generating an air flow within a room. In its preferred embodiment,
the present invention relates to a ceiling fan.
BACKGROUND OF THE INVENTION
[0003] A number of ceiling fans are known. A standard ceiling fan
comprises a set of blades mounted about a first axis and a drive
also mounted about the first axis for rotating the set of blades.
Another type of ceiling fan generates a column of air downwardly
into a room. For example, GB 2,049,161 describes a ceiling fan
which has a domed support which is suspended from a ceiling, and a
motor-driven impeller which is coupled to the inner surface of the
support. An air stream emitted from the impeller is conveyed
through a generally cylindrical body containing an array of air
passages to generate a linear air stream which is emitted from the
ceiling fan.
SUMMARY OF THE INVENTION
[0004] The present invention provides a ceiling fan comprising an
annular nozzle comprising an inner wall, an outer wall extending
about the inner wall, an air inlet, at least one air outlet, and an
interior passage located between the inner wall and the outer wall
for conveying an air flow to said at least one air outlet, the
inner wall defining a bore through which air from outside the
nozzle is drawn by the air flow emitted from said at least one air
outlet, and a support assembly for supporting the nozzle on a
ceiling, wherein the nozzle is rotatable relative to the support
assembly about a rotational axis and between a first orientation in
which the air flow is directed away from the ceiling and a second
orientation in which the air flow is directed towards the
ceiling.
[0005] The air flow emitted from the annular nozzle entrains air
surrounding the nozzle, which thus acts as an air amplifier to
supply both the emitted air flow and the entrained air to the user.
The entrained air will be referred to here as a secondary air flow.
The secondary air flow is drawn from the room space, region or
external environment surrounding the nozzle. The emitted air flow
combines with the entrained secondary air flow to form a combined,
or total, air flow projected forward from the nozzle. A portion of
the secondary air flow is drawn through the bore of the nozzle,
whereas other portions of the secondary air flow pass around the
outside of the outer wall and in front of the nozzle to combine
with the emitted air flow downstream of the bore.
[0006] The inner wall is preferably annular in shape to extend
about and define the bore. The interior passage is preferably
located between the inner wall and the outer wall, and more
preferably is defined, at least in part, by the inner wall and the
outer wall. The nozzle comprises at least one air inlet for
receiving an air flow. The outer wall preferably defines the air
inlet(s). For example, the, or each air inlet may be in the form of
an aperture formed in the outer wall. The nozzle comprises at least
one air outlet for emitting the air flow. The at least one air
outlet is preferably located in an air outlet section extending
between the inner wall and the outer wall. The air outlet section
may be a separate component connected between the inner wall and
the outer wall. Alternatively, at least part of the air outlet
section may be integral with one of the inner wall and the outer
wall. The air outlet section preferably forms at least part of an
end wall of the nozzle. As an alternative to forming the air
outlet(s) in the air outlet section, the air outlet(s) may be
located between the air outlet section and one of the inner wall
and the outer wall. The air inlet(s) of the nozzle are preferably
substantially orthogonal to the air outlet(s) of the nozzle.
[0007] The air outlet section is preferably configured to emit the
air flow away from the bore axis, preferably in the shape of an
outwardly tapering cone. We have found that the emission of the air
flow from the nozzle in a direction which extends away from the
bore axis can increase the degree of the entrainment of the
secondary air flow by the emitted air flow, and thus increase the
flow rate of the combined air flow generated by the fan. References
herein to absolute or relative values of the flow rate, or the
maximum velocity, of the combined air flow are made in respect of
those values as recorded at a distance of three times the diameter
of the air outlet of the nozzle.
[0008] Without wishing to be bound by any theory, we consider that
the rate of entrainment of the secondary air flow may be related to
the magnitude of the surface area of the outer profile of the air
flow emitted from the nozzle. When the emitted air flow is
outwardly tapering, or flared, the surface area of the outer
profile is relatively high, promoting mixing of the emitted air
flow and the air surrounding the nozzle and thus increasing the
flow rate of the combined air flow. Increasing the flow rate of the
combined air flow generated by the nozzle has the effect of
decreasing the maximum velocity of the combined air flow. This can
make the nozzle suitable for use with a fan for generating a flow
of air through a room or an office.
[0009] The air outlet section preferably comprises an inner section
connected to the inner wall, and an outer section connected to the
outer wall. The at least one air outlet may be located between the
inner section and the outer section of the annular wall. At least
part of the inner section may taper away from the bore axis. An
angle of inclination of this part of the inner section to the bore
axis may be between 0 and 45.degree.. This part of the inner
section preferably has a shape which is substantially conical. The
air outlet section may be arranged to emit the air flow in a
direction which is substantially parallel to this part of the inner
section. The outer section is preferably substantially orthogonal
to the bore axis.
[0010] The at least one air outlet preferably extends about the
bore axis. The nozzle may comprise a plurality of air outlets
angularly spaced about the bore axis, but in a preferred embodiment
the nozzle comprises a substantially annular air outlet.
[0011] The at least one air outlet may be shaped to emit air in a
direction extending away from the bore axis. A portion of the
interior passage which is located adjacent the air outlet may be
shaped to direct the air flow through the air outlet so that the
emitted air flow is directed away from the bore axis. To facilitate
manufacturing, the air outlet section may comprise an air channel
for directing the air flow through the air outlet. The air channel
is preferably inclined to the bore axis, and preferably has a shape
which is generally frusto-conical. An angle subtended between the
air channel and the bore axis is preferably between 0 and
45.degree.. In a preferred embodiment, this angle is around
15.degree.. The interior passage preferably extends about the bore
axis, and preferably surrounds the bore axis. The interior passage
may have any desired cross-section in a plane passing through the
bore axis. In a preferred embodiment the interior passage has a
substantially rectangular cross-section in a plane passing through
the bore axis.
[0012] The nozzle may comprise a chord line extending midway
between the inner wall and the outer wall of the nozzle. The at
least one air outlet is preferably located between the bore axis
and the chord line.
[0013] The ceiling fan includes a support assembly for supporting
the nozzle on a ceiling. The nozzle is rotatable relative to the
support assembly to allow a user to change the direction in which
the air flow is emitted into a room. The nozzle is rotatable
relative to the support assembly about a rotational axis and
between a first orientation in which the air flow is directed away
from the ceiling and a second orientation in which the air flow is
directed towards the ceiling. For example, during the summer the
user may wish to orient the nozzle so that the air flow is emitted
away from a ceiling to which the fan is attached and into a room so
that the air flow generated by the fan provides a relatively cool
breeze for cooling a user located beneath the fan. During the
winter however, the user may wish to invert the nozzle through
180.degree. so that the air flow is emitted towards the ceiling to
displace and circulate warm air which has risen to the upper
portions of the walls of the room, without creating a breeze
directly beneath the fan.
[0014] The nozzle may be inverted as it is rotated between the
first orientation and the second orientation. The rotational axis
of the nozzle is preferably substantially orthogonal to an axis of
the bore.
[0015] The ceiling fan preferably comprises an air inlet section
housing means for generating the air flow. The air inlet section is
preferably connected to the outer wall of the nozzle. The means for
generating the air flow preferably comprises an impeller and a
motor for rotating the impeller about an impeller axis to generate
the air flow. The rotational axis is preferably substantially
co-planar with the impeller axis.
[0016] The nozzle may be rotatable relative to both the air inlet
section and the support assembly. Alternatively, the air inlet
section may be connected to the support assembly so that both the
air inlet section and the nozzle are rotatable relative to the
support assembly.
[0017] The support assembly preferably comprises a mounting bracket
which is attachable to the ceiling of the room. This mounting
bracket may be in the form of a plate which is attachable to the
ceiling, for example using screws. The support assembly is
preferably configured to support the air inlet section and the
nozzle so that the impeller axis is at an angle of less than
90.degree. to the mounting bracket, more preferably so that the
impeller axis is at an angle of less than 45.degree. to the
mounting bracket. In one embodiment, the support assembly is
configured to support the air inlet section and the nozzle so that
the impeller axis is substantially parallel to the mounting
bracket. The bore axis is preferably substantially orthogonal to
the impeller axis, and so the support assembly may be configured to
support the air inlet section and the nozzle so that the axis of
the bore is substantially orthogonal to the mounting bracket. The
air inlet section and the nozzle preferably have substantially the
same depth as measured along the bore axis.
[0018] This can allow the fan assembly to be arranged so that it
lies substantially parallel to a horizontal ceiling to which the
mounting bracket is attached. The nozzle may be located relatively
close to the ceiling, reducing the risk of a user, or an item being
carried by the user, coming into contact with the nozzle.
[0019] An air inlet of the air inlet section may comprise a single
aperture, or a plurality of apertures through which the air flow is
drawn into the air inlet section. The air inlet is preferably
arranged so that the impeller axis passes through the air inlet,
more preferably so that the impeller axis is substantially
orthogonal to the air inlet of the air inlet section.
[0020] To minimise the size of the air inlet section, the impeller
is preferably an axial flow impeller. The air inlet section
preferably comprises a diffuser located downstream from the
impeller for guiding the air flow towards the nozzle. The air inlet
section preferably comprises an outer casing, a shroud extending
about the motor and the impeller, and a mounting arrangement for
mounting the shroud within the outer casing. The mounting
arrangement may comprise a plurality of mounts located between the
outer casing and the shroud, and a plurality of resilient elements
connected between the mounts and shroud. In addition to positioning
the shroud relative to the outer casing, preferably so that the
shroud is substantially co-axial with the outer casing, the
resilient elements can absorb vibrations generated during use of
the fan. The resilient elements are preferably held in a state of
tension between the mounts and the shroud, and preferably comprise
a plurality of tension springs each connected at one end to the
shroud and at another end to one of the supports. Means may be
provided for urging apart the ends of the tension springs in order
to maintain the springs in a state of tension. For example, the
mounting arrangement may comprise a spacer ring which is located
between the mounts for urging apart the mounts, and thereby urging
one end of each spring away from the other end.
[0021] The air inlet section is preferably located between the
support assembly and the nozzle. One end of the air inlet section
is preferably connected to the support assembly, with the other end
of the air inlet section being connected to the nozzle. The air
inlet section is preferably substantially cylindrical. Each of the
shroud and the outer casing may be substantially cylindrical.
[0022] The support assembly may comprise an air passage disposed
upstream of the air outlet(s). The air flow generated by the
impeller passes through the air passage. Depending on the relative
positions of the support assembly and the air inlet section, the
air passage may convey air to or from the air inlet section. For
example, the air passage of the support assembly may be
substantially co-axial with an air passage of the air inlet section
which houses the impeller and the motor. The rotational axis is
preferably substantially co-planar with a longitudinal axis of the
air passage. The longitudinal axis may pass through an air inlet of
the air passage, and may be substantially orthogonal to the air
inlet of the air passage.
[0023] The nozzle may be pivotable relative to at least part of the
support assembly. The support assembly preferably comprises a
ceiling mount for mounting the fan on a ceiling, an arm having a
first end connected to the ceiling mount, and a body connected to a
second end of the arm and to the nozzle. The second end of the arm
may be connected directly to the nozzle, or it may be connected to
the air inlet section. The body is preferably an annular body
including the air passage. The body is preferably pivotable
relative to the arm to move the nozzle between a raised position
and a lowered position. Lowering the nozzle can increase the
distance between the nozzle and a ceiling to which the fan is
attached, and so allow the nozzle to be rotated relative to the
support assembly without coming into contact with the ceiling.
Lowering the nozzle can also facilitate its rotation by the
user.
[0024] The nozzle is preferably pivotable relative to part of the
support assembly about a pivot axis which is substantially
orthogonal to the impeller axis. The pivot axis is preferably
substantially orthogonal to the bore axis of the nozzle. The
impeller axis is preferably substantially horizontal when the
nozzle is in the raised position and the support assembly is
connected to a substantially horizontal ceiling.
[0025] The nozzle may be pivotable about an angle in the range from
5 to 45.degree. to move from the raised position to the lowered
position. Depending on the radius of the outer wall of the nozzle,
the nozzle may pivot about an angle in the range from 10 to
20.degree. as it moves from the raised position to the lowered
position. The support assembly preferably houses a releasable
locking mechanism for maintaining the nozzle in its raised
position. The locking mechanism is releasable by the user to allow
the nozzle to be moved to its lowered position. The locking
mechanism is preferably biased towards a locking configuration for
locking the body relative to the arm so that the nozzle is
maintained in its raised position. The locking mechanism is
preferably arranged to return automatically to the locking
configuration when the nozzle is moved from the lowered position to
the raised position.
[0026] The arm is preferably rotatably connected to the ceiling
mount. The arm is preferably rotatable relative to the ceiling
mount about a rotational axis, and the arm is preferably inclined
to the rotational axis. Consequently, as the arm is rotated about
its rotational axis, the nozzle and the air inlet section orbit
about the rotational axis. This allows the nozzle to be moved to a
desired position within a relatively wide annular area. The arm is
preferably inclined at an angle in the range from 45 to 75.degree.
to the rotational axis to minimise the distance between the nozzle
and the ceiling. The rotational axis of the arm is preferably
substantially orthogonal to the pivot axis of the body.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Preferred features of the invention will now be described,
by way of example only, with reference to the accompanying
drawings, in which:
[0028] FIG. 1 is a front perspective view, from above, of a ceiling
fan;
[0029] FIG. 2 is a left side view of the ceiling fan mounted to a
ceiling, and with an annular nozzle of the ceiling fan in a raised
position;
[0030] FIG. 3 is a front view of the ceiling fan;
[0031] FIG. 4 is a rear view of the ceiling fan;
[0032] FIG. 5 is a top view of the ceiling fan;
[0033] FIG. 6 is a side sectional view of the ceiling fan, taken
along line A-A in FIG. 5;
[0034] FIG. 7 is a close up view of area A indicated in FIG. 6,
illustrating the motor and impeller of an air inlet section of the
ceiling fan;
[0035] FIG. 8 is a close up view of area B indicated in FIG. 6,
illustrating the air outlet of the annular nozzle;
[0036] FIG. 9 is a close up view of area D indicated in FIG. 6,
illustrating the connection between a ceiling mount and an arm of a
support assembly of the ceiling fan;
[0037] FIG. 10 is a side sectional view of the ceiling mount and
the arm of the support assembly, taken along line C-C in FIG.
6;
[0038] FIG. 11 is a close up view of area C indicated in FIG. 6,
illustrating a releasable locking mechanism for retaining the
annular nozzle in the raised position;
[0039] FIG. 12 is a sectional view of the locking mechanism, taken
along line B-B in FIG. 11; and
[0040] FIG. 13 is a left side view of the ceiling fan mounted to a
ceiling, and with an annular nozzle of the ceiling fan in a lowered
position.
DETAILED DESCRIPTION OF THE INVENTION
[0041] FIGS. 1 to 5 illustrate a fan assembly for generating an air
flow within a room. In this example, the fan assembly is in the
form of a ceiling fan 10 which is connectable to a ceiling C of a
room. The ceiling fan 10 comprises an air inlet section 12 for
generating the air flow, an annular nozzle 14 for emitting the air
flow, and a support assembly 16 for supporting the air inlet
section 12 and the nozzle 14 on the ceiling C of the room.
[0042] The air inlet section 12 comprises a generally cylindrical
outer casing 18 which houses a system for generating a primary air
flow which is emitted from the nozzle 14. As indicated in FIGS. 1,
2 and 5, the outer casing 18 may be formed with a plurality of
axially extending reinforcing ribs 20 which are spaced about the
longitudinal axis L of the outer casing 18, but these ribs 20 may
be omitted depending on the strength of the material from which the
outer casing 18 is formed.
[0043] With reference now to FIGS. 6 and 7, the air inlet section
12 houses an impeller 22 for drawing a primary air flow into the
ceiling fan 10. The impeller 22 is in the form of an axial flow
impeller which is rotatable about an impeller axis which is
substantially co-linear with the longitudinal axis L of the outer
casing 18. The impeller 22 is connected to a rotary shaft 24
extending outwardly from a motor 26. In this embodiment, the motor
26 is a DC brushless motor having a speed which is variable by a
control circuit (not shown) located within the support assembly 16.
The motor 26 is housed within a motor casing comprising a front
motor casing section 28 and a rear motor casing section 30. During
assembly, the motor 26 is inserted first into the front motor
casing section 28, and the rear motor casing section 30 is inserted
subsequently into the front casing section 28 to both retain and
support the motor 26 within the motor casing.
[0044] The air inlet section 12 also houses a diffuser located
downstream from the impeller 22. The diffuser comprises a plurality
of diffuser vanes 32 which are located between an inner cylindrical
wall 34 and an outer cylindrical wall of the diffuser. The diffuser
is preferably moulded as a single body, but alternatively the
diffuser may be formed from a plurality of parts or sections which
are connected together. The inner cylindrical wall 34 extends about
and supports the motor casing. The outer cylindrical wall provides
a shroud 36 which extends about the impeller 22 and the motor
casing. In this example, the shroud 36 is substantially
cylindrical. The shroud 36 comprises an air inlet 38 at one end
thereof through which the primary air flow enters the air inlet
section 12 of the ceiling fan 10, and an air outlet 40 at the other
end thereof through which the primary air flow is exhausted from
the air inlet section 12 of the ceiling fan 10. The impeller 22 and
the shroud 36 are shaped so when the impeller 22 and motor casing
are supported by the diffuser, the blade tips of the impeller 22
are in close proximity to, but do not contact, the inner surface of
the shroud 36 and the impeller 22 is substantially co-axial with
the shroud 36. A cylindrical guide member 42 is connected to the
rear of the inner cylindrical wall 34 of the diffuser for guiding
the primary air flow generated by the rotation of the impeller 22
towards the air outlet 40 of the shroud 36.
[0045] The air inlet section 12 comprises a mounting arrangement
for mounting the diffuser within the outer casing 18 so that the
impeller axis is substantially co-linear with the longitudinal axis
L of the outer casing 18. The mounting arrangement is located
within an annular channel 44 extending between the outer casing 18
and the shroud 36. The mounting arrangement comprises first mount
46 and a second mount 48 which is axially spaced along the
longitudinal axis L from the first mount 46. The first mount 46
comprises a pair of interconnected arcuate members 46a, 46b which
are mutually axially spaced along the longitudinal axis L. The
second mount 48 similarly comprises a pair of interconnected
arcuate members 48a, 48b which are mutually axially spaced along
the longitudinal axis L. An arcuate member 46a, 48a of each mount
46, 48 comprises a plurality of spring connectors 50, each of which
is connected to one end of a respective tension spring (not shown).
In this example, the mounting arrangement comprises four tension
springs, with each of these arcuate members 46a, 48a comprising two
diametrically opposed connectors 50. The other end of each tension
spring is connected to a respective spring connector 52 formed in
the shroud 36. The mounts 46, 48 are urged apart by an arcuate
spacer ring 54 inserted into the annular channel 44 between the
mounts 46, 48 so that the tension springs are held in a state of
tension between the connectors 50, 52. This serves to maintain a
regular spacing between the shroud 36 and the mounts 46, 48 while
allowing a degree of radial movement of the shroud 36 relative to
the mounts 46, 48 to reduce the transmission of vibrations from the
motor casing to the outer casing 18. A flexible seal 56 is provided
at one end of the annular channel 44 to prevent part of the primary
air flow from returning to the air inlet 40 of the shroud 36 along
the annular channel 44.
[0046] An annular mounting bracket 58 is connected to the end of
the outer casing 18 which extends about the air outlet 42 of the
shroud 36, for example by means of bolts 60. An annular flange 62
of the nozzle 14 of the ceiling fan 10 is connected to the mounting
bracket 58, for example, by means of bolts 64. Alternatively, the
mounting bracket 58 may be integral with the nozzle 14.
[0047] Returning to FIGS. 1 to 5, the nozzle 14 comprises an outer
section 70 and an inner section 72 connected to the outer section
70 at the upper end (as illustrated) of the nozzle. The outer
section 70 comprises a plurality of arcuate sections which are
connected together to define an outer side wall 74 of the nozzle
14. The inner section 72 similarly comprises a plurality of arcuate
sections which are each connected to a respective section of the
outer section 70 to define an annular inner side wall 76 of the
nozzle 14. The outer wall 74 extends about the inner wall 76. The
inner wall 76 extends about a central bore axis X to define a bore
78 of the nozzle. The bore axis X is substantially orthogonal to
the longitudinal axis L of the outer casing 18. The bore 78 has a
generally circular cross-section which varies in diameter along the
bore axis X. The nozzle also comprises an annular upper wall 80
which extends between one end of the outer wall 74 and one end of
the inner wall 76, and an annular lower wall 82 which extends
between the other end of the outer wall 74 and the other end of the
inner wall 76. The inner section 70 is connected to the outer
section 72 substantially midway along the upper wall 80, whereas
the outer section 72 of the nozzle forms the majority of the lower
wall 82.
[0048] With particular reference to FIG. 8, the nozzle 14 also
comprises an annular air outlet section 84. The outlet section 84
comprises an inner, generally frusto-conical inner section 86 which
is connected to the lower end of the inner wall 76. The inner
section 86 tapers away from the bore axis X. In this embodiment, an
angle subtended between the inner section 86 and the bore axis X is
around 15.degree.. The outlet section 84 also comprises an annular
outer section 88 which is connected to the lower end of the outer
section 70 of the nozzle 14, and which defines part of the annular
lower wall 82 of the nozzle. The inner section 86 and the outer
section 88 of the outlet section 84 are connected together by a
plurality of webs (not shown) which serve to control the spacing
between the inner section 86 and the outer section 88 about the
bore axis X. The outlet section 84 may be formed as a single body,
but it may be formed as a plurality of components which are
connected together. Alternatively, the inner section 86 may be
integral with the inner section 70 and the outer section 88 may be
integral with the outer section 72. In this case, one of the inner
section 86 and the outer section 88 may be formed with a plurality
of spacers for engaging the other one of the inner section 86 and
the outer section 88 to control the spacing between the inner
section 86 and the outer section 88 about the bore axis X.
[0049] The inner wall 76 may be considered to have a
cross-sectional profile in a plane containing the bore axis X which
is in the shape of part of a surface of an airfoil. This airfoil
has a leading edge at the upper wall 80 of the nozzle, a trailing
edge at the lower wall 82 of the nozzle, and a chord line CL
extending between the leading edge and the trailing edge. In this
embodiment, the chord line CL is generally parallel to the bore
axis X.
[0050] An air outlet 90 of the nozzle 14 is located between the
inner section 86 and the outer section 88 of the outlet section 84.
The air outlet 90 may be considered to be located in the lower wall
82 of the nozzle 14, adjacent to the inner wall 76 of the nozzle 14
and thus between the chord line CL and the bore axis X, as
illustrated in FIG. 6. The air outlet 90 is preferably in the form
of an annular slot. The air outlet 90 is preferably generally
circular in shape, and located in a plane which is perpendicular to
the bore axis X. The air outlet 90 preferably has a relatively
constant width in the range from 0.5 to 5 mm.
[0051] The annular flange 62 for connecting the nozzle 14 to the
air inlet section 12 is integral with one of the sections of the
outer section 70 of the nozzle. The flange 62 may be considered to
extend about an air inlet 92 of the nozzle for receiving the
primary air flow from the air inlet section 12. This section of the
outer section 70 of the nozzle 14 is shaped to convey the primary
air flow into an annular interior passage 94 of the nozzle 14. The
outer wall 74, inner wall 76, upper wall 80 and lower wall 82 of
the nozzle 14 together define the interior passage 94, which
extends about the bore axis X. The interior passage 94 has a
generally rectangular cross-section in a plane which passes through
the bore axis X.
[0052] As shown in FIG. 8, the air outlet section 84 comprises an
air channel 96 for directing the primary air flow through the air
outlet 90. The width of the air channel 96 is substantially the
same as the width of the air outlet 90. In this embodiment the air
channel 96 extends towards the air outlet 90 in a direction D
extending away from the bore axis X so that the air channel 96 is
inclined relative to the chord line CL of the airfoil, and to the
bore axis X of the nozzle 14.
[0053] The angle of inclination of the bore axis X, or the chord
line CL, to the direction D may take any value. The angle is
preferably in the range from 0 to 45.degree.. In this embodiment
the angle of inclination is substantially constant about the bore
axis X, and is around 15.degree.. The inclination of the air
channel 96 to the bore axis X is thus substantially the same as the
inclination of the inner section 86 to the bore axis X.
[0054] The primary air flow is thus emitted from the nozzle 14 in a
direction D which is inclined to the bore axis X of the nozzle 14.
The primary air flow is also emitted away from the inner wall 76 of
the nozzle 14. By controlling the shape of the air channel 96 so
that the air channel 96 extends away from the bore axis X, the flow
rate of the combined air flow generated by the ceiling fan 10 can
be increased in comparison to that of the combined air flow
generated when the primary air flow is emitted in a direction D
which is substantially parallel to the bore axis X, or which is
inclined towards the bore axis X. Without wishing to be bound by
any theory we consider this to be due to the emission of a primary
air flow having an outer profile with a relatively large surface
area. In this example, the primary air flow is emitted from the
nozzle 14 generally in the shape of an outwardly tapering cone.
This increased surface area promotes mixing of the primary air flow
with air surrounding the nozzle 14, increasing the entrainment of
the secondary air flow by the primary air flow and thereby
increasing the flow rate of the combined air flow.
[0055] Returning again to FIGS. 1 to 5, the support assembly 16
comprises a ceiling mount 100 for mounting the ceiling fan 10 on a
ceiling C, an arm 102 having a first end connected to the ceiling
mount 100 and a second end connected to a body 104 of the support
assembly 100. The body 104 is, in turn, connected to the air inlet
section 12 of the ceiling fan 10.
[0056] The ceiling mount 100 comprises a mounting bracket 106 which
is connectable to a ceiling C of a room using screws insertable
through apertures 108 in the mounting bracket 106. With reference
to FIGS. 9 and 10, the ceiling mount 100 further comprises a
coupling assembly for coupling a first end 110 of the arm 102 to
the mounting bracket 106. The coupling assembly comprises a
coupling disc 112 which has an annular rim 114 which is received
within an annular groove 116 of the mounting bracket 106 so that
the coupling disc 112 is rotatable relative to the mounting bracket
106 about a rotational axis R. The arm 102 is inclined to the
rotational axis R by an angle .theta. which is preferably in the
range from 45 to 75.degree., and in this example is around
60.degree.. Consequently, as the arm 102 is rotated about the
rotational axis R, the air inlet section 102 and the nozzle orbit
about the rotational axis R.
[0057] The first end 110 of the arm 102 is connected to the
coupling disc 112 by a number of coupling members 118, 120, 122 of
the coupling assembly. The coupling assembly is enclosed by an
annular cap 124 which is secured to the mounting bracket 106, and
which includes an aperture through which the first end 110 of the
arm 102 protrudes. The cap 124 also surrounds an electrical
junction box 126 for connection to electrical wires for supplying
power to the ceiling fan 10. An electrical cable (not shown)
extends from the junction box 126 through apertures 128, 130 formed
in the coupling assembly, and aperture 132 formed in the first end
100 of the arm, and into the air 102. As illustrated in FIGS. 9 to
11, the arm 102 is tubular, and comprises a bore 134 extending
along the length of the arm 102 and within which the electrical
cable extends from the ceiling mount 100 to the body 104.
[0058] The second end 136 of the arm 102 is connected to the body
104 of the support assembly 16. The body 104 of the support
assembly 16 comprises an annular inner body section 138 and an
annular outer body section 140 extending about the inner body
section 138. The inner body section 138 comprises an annular flange
142 which engages a flange 144 located on the outer casing 18 of
the air inlet section 12. An annular connector 146, for example a
C-clip, is connected to the flange 142 of the inner body section
138 so as to extend about and support the flange 144 of the outer
casing 18 so that the outer casing 18 is rotatable relative to the
inner body section 138 about the longitudinal axis L. An annular
inlet seal 148 forms an air-tight seal between the shroud 36 and
the flange 142 of the inner body section 138.
[0059] The air inlet section 12 and the nozzle 14, which is
connected to the outer casing 18 by the mounting bracket 58, are
thus rotatable relative to the support assembly 16 about the
longitudinal axis L. This allows a user to adjust the orientation
of the nozzle 14 relative to the support assembly 16, and thus
relative to a ceiling C to which the support assembly 16 is
connected. To adjust the orientation of the nozzle relative to the
ceiling C, the user pulls the nozzle 14 so that the air inlet
section 12 and the nozzle 14 both rotate about the longitudinal
axis L. For example, during the summer the user may wish to orient
the nozzle 14 so that the primary air flow is emitted away from the
ceiling C and into a room so that the air flow generated by the fan
provides a relatively cool breeze for cooling a user located
beneath the ceiling fan 10. During the winter however, the user may
wish to invert the nozzle 14 through 180.degree. so that the
primary air flow is emitted towards the ceiling C to displace and
circulate warm air which has risen to the upper portions of the
walls of the room, without creating a breeze directly beneath the
ceiling fan.
[0060] In this example, both the air inlet section 12 and the
nozzle 14 are rotatable about the longitudinal axis L.
Alternatively, the ceiling fan 10 may be arranged so that the
nozzle 14 is rotatable relative to the outer casing 18, and thus
relative to both the air inlet section 12 and the support assembly
16. For example, the outer casing 18 may be secured to the inner
body section 138 by means of bolts or screws, and the nozzle 14 may
be secured to the outer casing 18 in such a manner that it is
rotatable relative to the outer casing 18 about the longitudinal
axis L. In this case, the manner of connection between the nozzle
14 and the outer casing 18 may be similar to that affected between
the air inlet section 12 and the support assembly 16 in this
example.
[0061] Returning to FIG. 11, the inner body section 138 defines an
air passage 150 for conveying the primary air flow to the air inlet
38 of the air inlet section 12. The shroud 36 defines an air
passage 152 which extends through the air inlet section 12, and the
air passage 152 of the support assembly 16 is substantially
co-axial with the air passage 150 of the air inlet section 12. The
air passage 150 has an air inlet 154 which is orthogonal to the
longitudinal axis L.
[0062] The inner body section 138 and the outer body section 140
together define a housing 156 of the body 104 of the support
assembly 16. The housing 156 may retain a control circuit (not
shown) for supplying power to the motor 26. The electrical cable
extends through an aperture (not shown) formed in the second end
136 of the arm 102 and is connected to the control circuit. A
second electrical cable (not shown) extends from the control
circuit to the motor 26. The second electrical cable passes through
an aperture formed in the flange 142 of the inner body section 138
of the body 104 and enters the annular channel 44 extending between
the outer casing 18 and the shroud 36. The second electrical cable
subsequently extends through the diffuser to the motor 26. For
example, the second electrical cable may pass through a diffuser
vane 32 of the shroud and into the motor casing. A grommet may be
located about the second electrical cable to form an air-tight seal
with the peripheral surface of an aperture formed in the shroud 36
to inhibit the leakage of air through this aperture. The body 104
may also comprise a user interface which is connected to the
control circuit for allowing the user to control the operation of
the ceiling fan 10. For example, the user interface may comprise
one or more buttons or dials for allowing the user to activate and
de-activate the motor 26, and to control the speed of the motor 26.
Alternatively, or additionally, the user interface may comprise a
sensor for receiving control signals from a remote control for
controlling the operation of the ceiling fan 10.
[0063] Depending on the radius of the outer wall 74 of the nozzle
14, the length of the arm 102 and the shape of the ceiling to which
the ceiling fan 10 is connected, the distance between the
longitudinal axis L of the outer casing 18, about which the nozzle
14 rotates, and the ceiling may be shorter than the radius of the
outer wall 74 of the nozzle 14, which would inhibit rotation of the
nozzle through 90.degree. about the longitudinal axis L. In order
to allow the nozzle to be inverted, the body 104 of the support
assembly 16 is pivotable relative to the arm 102 about a first
pivot axis P1 to move the nozzle 14 between a raised position, as
illustrated in FIG. 2, and a lowered position, as illustrated in
FIG. 13. The first pivot axis P1 is illustrated in FIG. 11. The
first pivot axis P1 is defined by the longitudinal axis of a pin
158 which extends through the second end 136 of the arm 102, and
which has ends retained by the inner body section 138 of the body
104. The first pivot axis P1 is substantially orthogonal to the
rotational axis R about which the arm 102 rotates relative to the
ceiling mount 100. The first pivot axis P1 is also substantially
orthogonal to the longitudinal axis L of the outer casing 18.
[0064] In the raised position illustrated in FIG. 2, the
longitudinal axis L of the outer casing 18, and thus the impeller
axis, is substantially parallel to the mounting bracket 106. This
can allow the nozzle 14 to be oriented so that the bore axis X is
substantially perpendicular to the longitudinal axis L and to a
horizontal ceiling C to which the ceiling fan 10 is attached. In
the lowered position, the longitudinal axis L of the outer casing
18, and thus the impeller axis, is inclined to the mounting bracket
106, preferably by an angle of less than 90.degree. and more
preferably by an angle of less than 45.degree.. The body 104 may be
pivotable relative to the arm 102 about an angle in the range from
5 to 45.degree. to move the nozzle 14 from the raised position to
the lowered position. Depending on the radius of the outer wall 74
of the nozzle 14, a pivoting movement about an angle in the range
from 10 to 20.degree. may be sufficient to lower the nozzle
sufficiently to allow the nozzle to be inverted without contacting
the ceiling. In this example, the body 104 is pivotable relative to
the arm 102 about an angle of around 12 to 15.degree. to move the
nozzle 14 from the raised position to the lowered position.
[0065] The housing 156 of the body 104 also houses a releasable
locking mechanism 160 for locking the position of the body 104
relative to the arm 102. The locking mechanism 160 serves to retain
the body 104 in a position whereby the nozzle is in its raised
position. With reference to FIGS. 11 and 12, in this example the
locking mechanism 160 comprises a locking wedge 162 for engaging
the second end 136 of the arm 102 and an upper portion 164 of the
body 104 to inhibit relative movement between the arm 102 and the
body 104. The locking wedge 162 is connected to the inner body
section 138 for pivoting movement relative thereto about a second
pivot axis P2. The second pivot axis P2 is substantially parallel
to the first pivot axis P1. The locking wedge 162 is retained in a
locking position illustrated in FIG. 11 by a locking arm 166 which
extends about the inner body section 138 of the body 104. A locking
arm roller 168 is rotatably connected to the upper end of the
locking arm 166 to engage the locking wedge 162, and to minimise
frictional forces between the locking wedge 162 and the locking arm
166. The locking arm 166 is connected to the inner body section 138
for pivoting movement relative thereto about a third pivot axis P3.
The third pivot axis P3 is substantially parallel to the first
pivot axis P1 and the second pivot axis P2. The locking arm 166 is
biased towards the position illustrated in FIG. 11 by a resilient
element 170, preferably a spring, located between the locking arm
166 and the flange 142 of the inner body section 138.
[0066] To release the locking mechanism 160, the user pushes the
locking arm 166 against the biasing force of the resilient element
170 so as to pivot the locking arm 166 about the third pivot axis
P3. The outer body section 140 comprises a window 172 through which
a user may insert a tool to engage the locking arm 166.
Alternatively, a user operable button may be attached to the lower
end of the locking arm 166 so as to protrude through the window 172
for depression by the user. The movement of the locking arm 166
about the third pivot axis P3 moves the locking arm roller 168 away
from the second end 136 of the arm 102, thereby allowing the
locking wedge 162 to pivot about the second pivot axis P2 away from
its locking position and out of engagement with the second end 136
of the arm 102. The movement of the locking wedge 162 away from its
locking position allows the body 104 to pivot relative to the arm
102 about the first pivot axis P1 and so move the nozzle 14 from
its raised position to its lowered position.
[0067] Once the user has rotated the nozzle 14 about the
longitudinal axis L by the desired amount, the user can return the
nozzle 14 to its raised position by lifting the end of the nozzle
14 so that the body 104 pivots about the first pivot axis P1. As
the locking arm 166 is biased towards the position illustrated in
FIG. 11, the return of the nozzle 14 to its raised position causes
the locking arm 166 to return automatically to the position
illustrated in FIG. 11, and so return the locking wedge 162 to its
locking position.
[0068] To operate the ceiling fan 10 the user depresses an
appropriate button of the user interface or the remote control. A
control circuit of the user interface communicates this action to
the main control circuit, in response to which the main control
circuit activates the motor 26 to rotate the impeller 22. The
rotation of the impeller 22 causes a primary air flow to be drawn
into the body 104 of the support assembly 16 through the air inlet
150. The user may control the speed of the motor 26, and therefore
the rate at which air is drawn into the support assembly 16, using
the user interface or the remote control. The primary air flow
passes sequentially along the air passage 150 of the support
assembly 16 and the air passage 152 of the air inlet section 12, to
enter the interior passage 94 of the nozzle 14.
[0069] Within the interior passage 94 of the nozzle 14, the primary
air flow is divided into two air streams which pass in opposite
directions around the bore 78 of the nozzle 14. As the air streams
pass through the interior passage 94, air is emitted through the
air outlet 90. As viewed in a plane passing through and containing
the bore axis X, the primary air flow is emitted through the air
outlet 90 in the direction D. The emission of the primary air flow
from the air outlet 90 causes a secondary air flow to be generated
by the entrainment of air from the external environment,
specifically from the region around the nozzle. This secondary air
flow combines with the primary air flow to produce a combined, or
total, air flow, or air current, projected forward from the nozzle
14.
* * * * *