Technical Field
[0001] The present disclosure relates to a cross flow fan, a blowing device, and a refrigeration
cycle device.
Background Art
[0002] There is a known cross flow fan that includes fixing plates and blades that are resin
molded integrally with the fixing plates, an outer circumference ends of the blades
extending outward from the fixing plates (see Patent Literature 1, for example).
Citation List
Patent Literature
Summary of the Invention
Problems to be Solved by the Invention
[0004] The cross flow fan disclosed in Patent Literature 1 includes support rings (fixing
plates) and blades fixed to the support rings, and the outer end of each blade protrudes
outward from the outer circumference ends of the support rings. In other words, over
the entire circumference of the support rings, the support rings are present only
inward of the outer ends of the blades in a radial direction. In the prior art having
such a configuration, a portion of air flow that passes through between blades goes
around the end of the blade at portions having no support ring, and leaks from a positive
pressure surface to a negative pressure surface and hence, an air volume is reduced.
[0005] The present disclosure has been made to solve such a problem. The object of the present
disclosure is to provide a cross flow fan, a blowing device, and a refrigeration cycle
device that can achieve an increase in air volume without causing an increase in size
of the fan.
Solution to Problem
[0006] A cross flow fan according to the present disclosure includes: a plurality of support
rings arranged at a predetermined interval in a direction of a rotation axis; and
a plurality of blades provided between adjacent support rings, located close to an
outer circumference of a support ring of the adjacent support rings, and spaced apart
in a circumferential direction, a support ring of the plurality of support rings having
cutouts cut from an outer circumference end toward an inner circumference side, a
cutout of the cutouts being arranged at each position between adjacent blades, an
outer diameter of the support ring at the cutout being smaller than a distance from
the rotation axis to an outer end of a blade of the plurality of blades.
[0007] Or, a cross flow fan according to the present disclosure includes: a plurality of
support rings arranged at a predetermined interval in a direction of a rotation axis;
and a plurality of blades provided between the adjacent support rings, located close
to an outer circumference of the support ring, and spaced apart in a circumferential
direction, a surface of the support ring to which the blades are connected having
a plurality of protruding portions and a plurality of recessed portions alternately
arranged in a circumferential direction, the blades being connected to the plurality
of recessed portions of the support ring.
[0008] A blowing device according to the present disclosure includes: the cross flow fan
as described above.
[0009] A refrigeration cycle device according to the present disclosure includes: the cross
flow fan as described above; and a heat exchanger configured to perform heat exchange
between an air flow generated by the cross flow fan and a refrigerant.
Advantageous Effects of the Invention
[0010] According to the cross flow fan, the blowing device, and the refrigeration cycle
device according to the present disclosure, it is possible to obtain an advantageous
effect of achieving an increase in air volume without causing an increase in size
of the fan.
Brief Description of the Drawings
[0011]
Fig. 1 is a diagram showing the configuration of a refrigeration cycle device according
to Embodiment 1.
Fig. 2 is a cross-sectional view showing the configuration of indoor equipment of
an air-conditioning apparatus being an example of the refrigeration cycle device and
a blowing device according to Embodiment 1.
Fig. 3 is a front view of a cross flow fan according to Embodiment 1.
Fig. 4 is a cross-sectional view showing an example of an impeller of the cross flow
fan according to Embodiment 1.
Fig. 5 is a cross-sectional view showing an example of the impeller of the cross flow
fan according to Embodiment 1.
Fig. 6 is a cross-sectional view showing an example of the impeller of the cross flow
fan according to Embodiment 1.
Fig. 7 is a cross-sectional view showing an example of the impeller of the cross flow
fan according to Embodiment 1.
Fig. 8 is a cross-sectional view showing an example of the impeller of the cross flow
fan according to Embodiment 1.
Fig. 9 is a cross-sectional view showing an example of the impeller of the cross flow
fan according to Embodiment 1.
Fig. 10 is a cross-sectional view showing an example of the impeller of the cross
flow fan according to Embodiment 1.
Fig. 11 is a perspective view showing a modification of the impeller of the cross
flow fan according to Embodiment 1.
Fig. 12 is a front view showing the modification of the impeller of the cross flow
fan according to Embodiment 1.
Fig. 13 is an enlarged cross-sectional view of a main part, showing the modification
of the impeller of the cross flow fan according to Embodiment 1.
Fig. 14 is a perspective view showing a modification of the impeller of the cross
flow fan according to Embodiment 1.
Description of Embodiment
[0012] Modes for carrying out a cross flow fan, a blowing device, and a refrigeration cycle
device according to the present disclosure will be described with reference to attached
drawings. In the respective drawings, identical or corresponding components are given
the same reference symbols, and the repeated description will be simplified or omitted
when appropriate. In the description made hereinafter, for the sake of convenience,
the positional relationship of respective structures may be expressed with reference
to the states shown in the drawings. The present disclosure is not limited to the
following embodiments, and respective embodiments may be freely combined, optional
constitutional elements of the respective embodiments may be modified, or optional
constitutional elements of the respective embodiments may be omitted without departing
from the gist of the present disclosure.
Embodiment 1.
[0013] An embodiment 1 of the present disclosure will be described with reference to Fig.
1 to Fig. 14. Fig. 1 is a diagram showing the configuration of a refrigeration cycle
device. Fig. 2 is a cross-sectional view showing the configuration of indoor equipment
of an air-conditioning apparatus being an example of the refrigeration cycle device
and a blowing device. Fig. 3 is a front view of a cross flow fan. Fig. 4 to Fig. 10
are cross-sectional views showing examples of an impeller of the cross flow fan. Fig.
11 is a perspective view showing a modification of the impeller of the cross flow
fan. Fig. 12 is a front view showing the modification of the impeller of the cross
flow fan. Fig. 13 is an enlarged cross-sectional view of a main part, showing the
modification of the impeller of the cross flow fan. Fig. 14 is a perspective view
showing a modification of the impeller of the cross flow fan.
[0014] Fig. 1 shows a configuration of the air-conditioning apparatus being an example of
the refrigeration cycle device that includes the cross flow fan according to the present
disclosure. Examples of the refrigeration cycle device that includes the cross flow
fan according to the present disclosure include a showcase in addition to the air-conditioning
apparatus. As will be described later, the air-conditioning apparatus has a function
of blowing air. Accordingly, the air-conditioning apparatus described herein is also
an example of a blowing device that includes the cross flow fan according to the present
disclosure. Examples of the blowing device that includes the cross flow fan according
to the present disclosure include for example a circulator and a tower fan in addition
to the air-conditioning apparatus.
[0015] As shown in Fig. 1, the air-conditioning apparatus being the refrigeration cycle
device according to the present embodiment includes indoor equipment 10 and outdoor
equipment 20. The indoor equipment 10 is installed inside a room that is the target
of air conditioning, that is, in a room. The outdoor equipment 20 is installed outside
the room, that is, outdoors. The indoor equipment 10 includes an indoor equipment
heat exchanger 11 and a cross flow fan 100. The outdoor equipment 20 includes an outdoor
equipment heat exchanger 21, an outdoor equipment fan 22, a compressor 23, an expansion
valve 24, and a four-way valve 25.
[0016] The indoor equipment 10 and the outdoor equipment 20 are connected with each other
by refrigerant pipes 30. The refrigerant pipes 30 are provided between the indoor
equipment heat exchanger 11 of the indoor equipment 10 and the outdoor equipment heat
exchanger 21 of the outdoor equipment 20 in a state that allows circulation. A refrigerant
is sealed in the refrigerant pipes 30. An example of the refrigerant sealed in the
refrigerant pipes 30 includes difluoromethane (CH2F2:R32).
[0017] The refrigerant pipes 30 sequentially connect the indoor equipment heat exchanger
11, the four-way valve 25, the compressor 23, the outdoor equipment heat exchanger
21, and the expansion valve 24. Accordingly, a refrigerant circuit is formed in which
a refrigerant circulates between the indoor equipment heat exchanger 11 and the outdoor
equipment heat exchanger 21.
[0018] The compressor 23 is equipment that compresses a supplied refrigerant to increase
the pressure and the temperature of the refrigerant. For the compressor 23, a rotary
compressor, a scroll compressor, a reciprocating compressor, or the like may be used,
for example. The expansion valve 24 expands the refrigerant, condensed by the outdoor
equipment heat exchanger 21, to reduce the pressure of the refrigerant.
[0019] The indoor equipment heat exchanger 11 causes the refrigerant that flows into the
indoor equipment heat exchanger 11 to exchange heat with air around the indoor equipment
heat exchanger 11. The cross flow fan 100 blows air in such a way as to cause indoor
air to pass through an area around the indoor equipment heat exchanger 11, thus promoting
heat exchange between the refrigerant and air in the indoor equipment heat exchanger
11, and sending the air heated or cooled by the heat exchange into the room again.
The outdoor equipment heat exchanger 21 causes the refrigerant that flows into the
outdoor equipment heat exchanger 21 to exchange heat with air around the outdoor equipment
heat exchanger 21. The outdoor equipment fan 22 blows air in such a way as to cause
outdoor air to pass through an area around the outdoor equipment heat exchanger 21,
thus promoting heat exchange between the refrigerant and air in the outdoor equipment
heat exchanger 21.
[0020] In the refrigerant circuit having such a configuration, heat exchange between a refrigerant
and air is performed in each of the indoor equipment heat exchanger 11 and the outdoor
equipment heat exchanger 21 and hence, the refrigerant circuit serves as a heat pump
that transfers heat between the indoor equipment 10 and the outdoor equipment 20.
When the four-way valve 25 is switched, a circulating direction of the refrigerant
in the refrigerant circuit is reversed, so that a cooling operation and a heating
operation of the air-conditioning apparatus can be switched.
[0021] As shown in Fig. 2, the indoor equipment 10 includes a housing 12. The housing 12
is installed in the room. The indoor equipment heat exchanger 11 and the cross flow
fan 100 are housed in the housing 12. An upper surface portion of the housing 12 has
an air inlet 13. The air inlet 13 is an opening through which air is taken into the
housing 12 from the outside. A lower surface of the housing 12 has an air outlet 14.
The air outlet 14 is an opening through which air is discharged to the outside from
the inside of the housing 12.
[0022] An air passage extending from the air inlet 13 to the air outlet 14 is formed in
the housing 12. A filter 15 is installed in the air inlet 13. The filter 15 is provided
to remove relatively large refuse, dust, dirt, and the like from air that flows into
the housing 12 through the air inlet 13.
[0023] In the air passage in the housing 12, the indoor equipment heat exchanger 11 is installed
on the downwind side of the filter 15. The indoor equipment heat exchanger 11 performs
heat exchange with air flowing through the air passage in the housing 12, thus heating
or cooling the air flowing through the air passage. Whether air is heated or cooled
depends on whether the air-conditioning apparatus is performing a heating operation
or a cooling operation.
[0024] In the above-described air passage, the cross flow fan 100 is installed on the downwind
side of the indoor equipment heat exchanger 11. The cross flow fan 100 is provided
to generate, in the air passage in the housing 12, an air flow directing to the air
outlet 14 from the air inlet 13. In the housing 12, a rear guide 17 is provided on
the rear surface side of the impeller of the cross flow fan 100. Further, in the housing
12, a stabilizer 18 is provided on the front surface side of the impeller of the cross
flow fan 100. The rear guide 17 is disposed to have a helical shape in which a distance
from the impeller of the cross flow fan 100 increases as the rear guide 17 approaches
the air outlet 14 from the indoor equipment heat exchanger 11. Due to the rear guide
17 and the stabilizer 18, during rotation of the impeller of the cross flow fan 100,
it is possible to achieve a flow of air in which air is suctioned from an area having
the smallest flow passage resistance, that is, an area close to the indoor equipment
heat exchanger 11, and the air is blown out toward an area having the second smallest
flow passage resistance, that is, an area close to the air outlet 14.
[0025] An up-down vane 16 is provided to the air outlet 14. The up-down vane 16 is provided
to adjust a blowing angle of air to be blown out from the air outlet 14. By changing
the direction of the up-down vane 16, the indoor equipment 10 can change an air blowing
direction in an up-down direction. Although not shown in the drawing, a left-right
vane is also provided to the air outlet 14. The left-right vane is provided to adjust
a blowing angle of air to be blown out from the air outlet 14 in a left-right direction.
[0026] When the cross flow fan 100 is operated, an air flow directing toward the air outlet
14 from the air inlet 13 is generated in the air passage, so that air is suctioned
from the air inlet 13 and the air is blown out from the air outlet 14. The air suctioned
from the air inlet 13 forms an air flow that passes through the filter 15, the indoor
equipment heat exchanger 11, and the cross flow fan 100 in this order along the air
passage in the housing 12, and is blown out from the air outlet 14. At this point
of operation, the up-down vane 16 and the left-right vane disposed on the downwind
side of the cross flow fan 100 adjust a direction of air to be blown out from the
air outlet 14, that is, the air blowing direction. The indoor equipment 10 of the
air-conditioning apparatus having the above-mentioned configuration blows air into
a room. The indoor equipment 10 can change the temperature and the direction of the
air flow to be blown.
[0027] As shown in Fig. 3, the cross flow fan 100 includes an impeller 110 and a motor 150.
The impeller 110 includes support rings 120, blades 130, and a rotation axis 140.
The motor 150 rotates the impeller 110 about the rotation axis 140.
[0028] The impeller 110 includes a plurality of support rings 120. The support ring 120
is a flat plate member having a ring shape. The plurality of support rings 120 are
arranged at predetermined intervals in a direction parallel to the rotation axis 140
(hereinafter also referred to as "direction of the rotation axis 140"). The rotation
axis 140 of the impeller 110 is provided in such a way as to penetrate through the
center of the ring shape of each of the plurality of support rings 120. The plurality
of blades 130 are provided between adjacent support rings 120. The plurality of blades
130 are provided at a position close to the outer circumference of the support ring
120. The plurality of blades 130 are aligned in a spaced-apart manner along the circumferential
direction of the support ring 120.
[0029] Each of the plurality of blades 130 have the same cross sectional shape. Referring
to Fig. 10, for example, each of the plurality of blades 130 has a positive pressure
surface 131 and a negative pressure surface 132, and an outer end 133 and an inner
end 134. The positive pressure surface 131 is the surface of the blade 130 that faces
in a rotation direction. The negative pressure surface 132 is the surface of the blade
130 that faces in a direction opposite to the rotation direction. The outer end 133
is the end of the blade 130 that is farthest from the rotation axis 140. The inner
end 134 is the end of the blade 130 that is closest to the rotation axis 140.
[0030] When attention is focused on the support rings 120 disposed at intermediate positions,
excluding both ends, as shown in Fig. 3, the blades 130 are connected to each of both
flat plate surfaces of each support ring 120 at the intermediate position. One surface
of the support ring 120 is assumed as a first surface, and the other surface of the
support ring 120 is assumed as a second surface. That is, the second surface is the
surface on the back side of the first surface. In this case, the blades 130 are connected
to the first surface of the support ring 120, and the blades 130 are also connected
to the second surface of the same support ring 120. In the configuration example shown
in Fig. 3, positions of the blades 130 connected to the first surface of the support
ring 120 and positions of the blades 130 connected to the second surface of the same
support ring 120 are located in such a way as to prevent overlapping.
[0031] In the cross flow fan 100 according to the present embodiment, the support ring 120
has cutouts 121. Next, the configurations of the support ring 120 particularly relating
to the cutouts 121 will be described with reference to Fig. 4 to Fig. 9. The cutouts
121 are cut from the outer circumference end of the support ring 120 toward the inner
circumference side. Each of the cutouts 121 is provided at each position between adjacent
blades 130 on the one surface of the support ring 120. The outer end 133 of each blade
130 is disposed on the support ring 120 at a portion at which the cutout 121 is not
formed. In these configuration examples, the number of cutouts 121 formed on one support
ring 120 is equal to the number of blades 130 connected to the support ring 120.
[0032] An outer diameter of the support ring 120 at the cutout 121 is smaller than a distance
from the rotation axis 140 to the outer end of the blade 130. The outer diameter of
the support ring 120 at the cutout 121 is, for example, a distance from the rotation
axis 140 to the cutout bottom of the cutout 121 (the deepest portion of the cutout).
In other words, it can be also said that the cutout bottom of the cutout 121 is the
portion of the support ring 120 having the smallest outer diameter.
[0033] According to the cross flow fan 100 having the above-mentioned configuration, by
providing the cutouts 121 to the support ring 120 at a position close to the outer
ends 133 of the blades 130, air flow from between the blades 130 also flows into spaces
in the cutouts 121. Therefore, at a portion at which each cutout 121 is provided,
air flow from between the blades 130 easily flows into the area downstream of the
support ring 120. In contrast, the cutouts 121 are not provided to the support ring
120 at a position close to the inner ends 134 of the blades 130 and hence, it is possible
to suppress generation of a flow that goes around the inner end 134 of the blade 130.
Accordingly, it is possible to reduce low wind speed areas in the area downstream
of the support ring 120 and hence, it is possible to achieve an increase in air volume
of the cross flow fan 100 without causing an increase in size of the fan. It is also
possible to obtain an advantageous effect of reducing noise when a comparison is made
at the same fan input.
[0034] In the configuration examples shown in Fig. 4 and Fig. 5, the cutouts 121 have a
trapezoidal shape. Fig. 4 shows the configuration example of the support ring 120
disposed at both ends in the direction of the rotation axis 140. When the description
is made with reference to Fig. 4, each cutout 121 is provided at each position between
the adjacent blades 130. The outer end 133 of each blade 130 is disposed on the support
ring 120 at a portion at which the cutout 121 is not formed. An outer diameter A of
the support ring 120 at the cutout 121 is smaller than a distance B from the rotation
axis 140 to the outer end of the blade 130.
[0035] Fig. 5 shows the configuration example of the support ring 120 at the intermediate
position, excluding both ends. As described above, positions of the blades 130 connected
to the first surface, being the one surface of the support ring 120 at the intermediate
position, and positions of the blades 130 connected to the second surface, being the
other surface of the same support ring 120, are located in such a way as to prevent
overlapping. Therefore, as shown in Fig. 5, two cutouts 121 are disposed between blades
130 connected to the first surface of the support ring 120. In the same manner, two
cutouts 121 are disposed between blades 130 connected to the second surface of the
support ring 120.
[0036] In the configuration examples shown in Fig. 6 and Fig. 7, the cutouts 121 have a
V shape. Each cutout 121 is disposed in a side of the rotation direction than the
intermediate position between adjacent blades 130. A portion of each cutout 121 extends
along the shape of the negative pressure surface 132 of each blade 130. Fig. 6 shows
the configuration example of a support ring 120 at both ends in the direction of the
rotation axis 140. Fig. 7 shows the configuration example of a support ring 120 at
the intermediate position, excluding both ends. When the description is made with
reference to Fig. 6, each cutout 121 is provided at each position between adjacent
blades 130. The outer end 133 of each blade 130 is disposed on the support ring 120
at a portion at which the cutout 121 is not formed. The outer diameter A of the support
ring 120 at the cutout 121 is smaller than the distance B from the rotation axis 140
to outer end of the blade 130.
[0037] An arrow shown in Fig. 6 indicates the rotation direction of the impeller 110. Each
cutout 121 is disposed in the side of the rotation direction than the intermediate
position between adjacent blades 130. That is, a distance from the cutout 121 to the
positive pressure surface 131 of the blade 130 in the counter-rotation direction is
larger than a distance from the cutout 121 to the negative pressure surface 132 of
the blade 130 in the rotation direction. At a portion indicated by "C" in the drawing,
the cutout 121 extends along the negative pressure surface 132 of the blade 130.
[0038] The positive pressure surface 131 side of each blade 130 has a high pressure and
hence, if the cutout 121 is provided in the vicinity of the positive pressure surface
131 side of each blade 130, an air flow easily leaks from the cutouts 121. Such a
configuration causes turbulence of the air flow to be easily generated due to a flow
that goes around the outer end 133 of the blade 130. In view of the above, each cutout
121 is disposed in the side of the rotation direction than the intermediate position
between adjacent blades 130. With such a configuration, it is possible to suppress
the generation of a flow that goes around the outer end 133 of the blade 130 on the
positive pressure surface 131 side of the blade 130.
[0039] In the configuration examples shown in Fig. 8 and Fig. 9, cutouts 121 have a V shape.
The width of each cutout 121 in the rotation direction from the portion of a support
ring 120 having the smallest outer diameter is smaller than the width of the cutout
121 in the counter-rotation direction from the portion of the support ring 120 having
the smallest outer diameter. Fig. 8 shows the configuration example of the support
ring 120 at both ends in the direction of the rotation axis 140. Fig. 9 shows the
configuration example of the support ring 120 at the intermediate position, excluding
both ends. When the description is made with reference to Fig. 8, each cutout 121
is provided at each position between adjacent blades 130. The outer end 133 of each
blade 130 is disposed on the support ring 120 at a portion at which the cutout 121
is not formed. An outer diameter A of the support ring 120 at the cutout 121 is smaller
than a distance B from the rotation axis 140 to the outer end of the blade 130.
[0040] An arrow shown in Fig. 8 indicates the rotation direction of the impeller 110. The
width of the cutout 121 in the rotation direction from the portion of the support
ring 120 having the smallest outer diameter, that is, from the cutout bottom, is indicated
by "E" in the drawing. The width of the cutout 121 in the counter-rotation direction
from the cutout bottom is indicated by "F" in the drawing. The width E in the rotation
direction from the cutout bottom is smaller than the width F in the counter-rotation
direction from the cutout bottom. In the same manner as the configuration examples
shown in Fig. 6 and Fig. 7, also in the configuration examples shown in Fig. 8 and
Fig. 9, a portion of each cutout 121 extends along the shape of the negative pressure
surface 132 of the blade 130.
[0041] In each cutout 121 having a V shape as shown in Fig. 8 and Fig. 9, in an area indicated
by "F" in Fig. 8, an inclined surface is formed on the outer circumference of the
support ring 120, the inclined surface approaching the rotation axis 140 as the inclined
surface extends in the rotation direction. When the inclined surface on the outer
circumference of the support ring 120 pushes air, a centrifugal force acts on the
air and hence, an air flow blown out toward the area downstream of the support ring
120 is accelerated by the centrifugal force and hence, it is possible to further increase
an air volume. In the configuration examples shown in Fig. 8 and Fig. 9, the width
of the cutout 121 in the rotation direction from the cutout bottom is smaller than
the width of the cutout 121 in the counter-rotation direction from the cutout bottom.
Accordingly, inclination of each inclined surface, which approaches the rotation axis
140 as the inclined surface extends in the rotation direction, is small and hence,
it is possible to suppress turbulence caused by collision of air flows caused when
the inclined surfaces push air. In contrast, in an area indicated by "E" in Fig. 8,
an inclined surface is formed on the outer circumference of the support ring 120,
the inclined surface being away from the rotation axis 140 as the inclined surface
extends in the rotation direction. Due to a negative pressure generated on the inclined
surfaces on the outer circumference of the support ring 120, an air flow can be easily
drawn into the area downstream of the support ring 120 and hence, it is possible to
further reduce low wind speed areas in the area downstream of the support ring 120.
[0042] In the configurations as shown in Fig. 6 to Fig. 9 in which a portion of each cutout
121 extends along the shape of the negative pressure surface 132 of the blade 130,
the end surface of the support ring 120 at a portion of each cutout 121 that extends
along the shape of the negative pressure surface 132 of the blade 130 may integrally
form a blade surface with the negative pressure surface 132 of the blade 130. With
such a configuration, it is possible to increase the area of the negative pressure
surface 132 of each blade 130 by an amount corresponding to the thickness of the support
ring 120. Accordingly, it is possible to achieve an increase in air volume by increasing
the effective area of blades for generating air flow.
[0043] As a modification of the cross flow fan 100 according to the present embodiment,
the positions of the blades 130 connected to the first surface, being the one surface
of the support ring 120 at the intermediate position, and the positions of the blades
130 connected to the second surface, being the other surface of the same support ring
120, may be located in such a way as to overlap with each other. In this case, the
configuration of the support ring 120 is equal to the configuration of the support
ring 120 at both ends in the direction of the rotation axis 140, which has been described
heretofore. That is, as shown in Fig. 4, Fig. 6, and Fig. 8, one cutout 121 is disposed
at each position between blades 130 connected to the first surface of the support
ring 120. In the same manner, one cutout 121 is also disposed at each position between
blades 130 connected to the second surface of the support ring 120. In this case,
the number of cutouts 121 formed on one support ring 120 is equal to the number of
blades 130 connected to one surface of the support ring 120.
[0044] Next, the description will be made with reference to Fig. 10. As shown in Fig. 10,
an inner diameter of the support ring 120 having a ring shape is assumed as "D1".
Further, a distance from the rotation axis 140 to the inner end of the blade 130 is
assumed as "D2". In the cross flow fan 100 according to the present embodiment, it
is preferable to set the inner diameter D1 of the support ring 120 to be equal to
or more than half of the distance D2 from the rotation axis 140 to the inner end of
the blade 130, that is, equal to or more than D2/2, and equal to or less than the
distance D2 from the rotation axis 140 to the inner end of the blade 130.
[0045] By setting the inner diameter D1 of the support ring 120 to be equal to or less than
the distance D2 from the rotation axis 140 to the inner end of the blade 130, it is
possible to suppress generation of turbulence of an air flow caused by an air flow
that goes around the inner end 134 of the blade 130. Further, by setting the inner
diameter D1 of the support ring 120 to be equal to or less than the distance D2 from
the rotation axis 140 to the inner end of the blade 130, a circulating vortex generated
in the impeller 110 is divided by the support ring 120 and hence, it is possible to
suppress destabilization of the flow caused by circulating vortexes that form continuously
and affect with each other. In contrast, a region in which the distance from the rotation
axis 140 is equal to or less than D2/2 is less affected by circulating vortexes that
form continuously. In view of the above, by setting the inner diameter D1 of the support
ring 120 to be equal to or more than D2/2, the amount of a material necessary for
the support ring 120 is reduced and hence, it is possible to achieve a reduction in
weight. Accordingly, by setting the inner diameter D1 of the support ring 120 to be
equal to or more than half of the distance D2 from the rotation axis 140 to the inner
end of the blade 130, that is, equal to or more than D2/2, and equal to or less than
the distance D2 from the rotation axis 140 to the inner end of the blade 130, it is
possible to achieve both suppression of destabilization of the air flow in the impeller
110 and a reduction in weight of the impeller 110.
[0046] Next, a modification of the cross flow fan 100 according to the present embodiment
will be described with reference to Fig. 11 to Fig. 13. In the present modification,
as shown in Fig. 11 to Fig. 13, a support ring 120 is caused to have a corrugated
plate shape instead of a flat plate shape. The surface of the support ring 120 to
which the blades 130 are connected has a plurality of protruding portions 122 and
a plurality of recessed portions 123 that are alternately arranged in the circumferential
direction. Positions of the protruding portions 122 on the first surface of the support
ring 120 correspond to the recessed portions 123 on the second surface. Positions
of the recessed portions 123 on the first surface of the support ring 120 correspond
to the protruding portions 122 on the second surface. In other words, the back side
of each protruding portion 122 on the one surface of the support ring 120 forms the
recessed portion 123. Further, the back side of each recessed portion 123 on the one
surface of the support ring 120 forms the protruding portion 122. The protruding portions
122 and the recessed portions 123 are disposed to extend in the radial direction in
a state of being bent in conformity with the cross sectional shapes of the blades
130.
[0047] The blades 130 are connected to the recessed portions 123 of the support ring 120.
The end of each blade 130 is connected to each recessed portion 123 by welding, for
example, so that the blades 130 are fixed to the support ring 120. In fixing the blades
130, it is preferable to provide a flat surface part to the bottom of each recessed
portion 123, and to connect the end of each blade 130 to each flat surface part. With
such a configuration, it is possible to increase welding strength of the blades 130
to the support ring 120.
[0048] As described above, the back side of each recessed portion 123 forms the protruding
portion 122 and hence, the recessed portions 123 on the first surface of the support
ring 120 and the recessed portions 123 on the second surface are inevitably disposed
in such a way as to prevent overlapping. Accordingly, by connecting the blades 130
to the recessed portions 123 of the support ring 120, positions of the blades 130
connected to the first surface of the support ring 120 and positions of the blades
130 connected to the second surface are located in such a way as to prevent overlapping.
[0049] According to the modification of the cross flow fan 100 having the above-mentioned
configuration, it is possible to increase the blade width, in the direction of the
rotation axis 140, of each blade 130 disposed between the support rings 120 without
significantly changing the entire width of the impeller 110 in the direction of the
rotation axis 140. Therefore, it is possible to achieve an increase in air volume
by increasing the effective area of blades for generating air flow.
[0050] As shown in Fig. 14, a configuration may be adopted in which the protruding portions
122 and the recessed portions 123 are provided to the support ring 120 having no cutout
121, and the blades 130 are connected to the recessed portions 123 of the support
ring 120. Also in such a configuration, it is possible to increase the blade width,
in the direction of the rotation axis 140, of each blade 130 disposed between the
support rings 120 without significantly changing the entire width of the impeller
110 in the direction of the rotation axis 140. Therefore, it is possible to achieve
an increase in air volume by increasing the effective area of blades for generating
air flow.
Industrial Applicability
[0051] The present disclosure is applicable to a cross flow fan including a plurality of
support rings arranged at predetermined intervals in the direction of a rotation axis,
and a plurality of blades provided between adjacent support rings, located close to
the outer circumference of the support ring, and spaced apart in the circumferential
direction. The present disclosure is also applicable to a blowing device and a refrigeration
cycle device that includes the cross flow fan.
Reference Signs List
[0052]
- 10
- Indoor equipment
- 11
- Indoor equipment heat exchanger
- 12
- Housing
- 13
- Air inlet
- 14
- Air outlet
- 15
- Filter
- 16
- Up-down vane
- 17
- Rear guide
- 18
- Stabilizer
- 20
- Outdoor equipment
- 21
- Outdoor equipment heat exchanger
- 22
- Outdoor equipment fan
- 23
- Compressor
- 24
- Expansion valve
- 25
- Four-way valve
- 30
- Refrigerant pipe
- 100
- Cross flow fan
- 110
- Impeller
- 120
- Support ring
- 121
- Cutout
- 122
- Protruding portion
- 123
- Recessed portions
- 130
- Blade
- 131
- Positive pressure surface
- 132
- Negative pressure surface
- 133
- Outer end
- 134
- Inner end
- 140
- Rotation axis
- 150
- Motor
1. A cross flow fan comprising:
a plurality of support rings arranged at a predetermined interval in a direction of
a rotation axis; and
a plurality of blades provided between adjacent support rings, located close to an
outer circumference of a support ring of the adjacent support rings, and spaced apart
in a circumferential direction,
a support ring of the plurality of support rings having cutouts cut from an outer
circumference end toward an inner circumference side, a cutout of the cutouts being
arranged at each position between adjacent blades,
an outer diameter of the support ring at the cutout being smaller than a distance
from the rotation axis to an outer end of a blade of the plurality of blades.
2. The cross flow fan according to claim 1, wherein a portion of the cutout extends along
a shape of a negative pressure surface of the blade.
3. The cross flow fan according to claim 2, wherein an end surface of the support ring
at the portion of the cutout that extends along the shape of the negative pressure
surface of the blade integrally forms a blade surface with the negative pressure surface
of the blade.
4. The cross flow fan according to any one of claim 1 to claim 3, wherein a width of
the cutout in a rotation direction from a portion of the support ring having a smallest
outer diameter is smaller than a width of the cutout in a counter-rotation direction
from the portion.
5. The cross flow fan according to any one of claim 1 to claim 3, wherein the cutout
is disposed in a side of a rotation direction than an intermediate position of the
adjacent blades.
6. The cross flow fan according to any one of claim 1 to claim 5, wherein the number
of cutouts formed on the support ring is equal to the number of blades connected to
the support ring.
7. The cross flow fan according to any one of claim 1 to claim 6, wherein an inner diameter
of the support ring is equal to or more than half of a distance from the rotation
axis to an inner end of the blade, and equal to or less than the distance from the
rotation axis to the inner end of the blade.
8. The cross flow fan according to any one of claim 1 to claim 7, wherein positions of
the blades connected to a first surface of the support ring and positions of the blades
connected to a second surface are located in such a way as to prevent overlapping,
the second surface being a back side of the first surface.
9. The cross flow fan according to any one of claim 1 to claim 8, wherein a surface of
the support ring to which the blades are connected has a plurality of protruding portions
and a plurality of recessed portions alternately arranged in the circumferential direction,
and
the blades are connected to the plurality of recessed portions of the support ring.
10. A cross flow fan comprising:
a plurality of support rings arranged at a predetermined interval in a direction of
a rotation axis; and
a plurality of blades provided between the adjacent support rings, located close to
an outer circumference of the support ring, and spaced apart in a circumferential
direction,
a surface of the support ring to which the blades are connected having a plurality
of protruding portions and a plurality of recessed portions alternately arranged in
a circumferential direction,
the blades being connected to the plurality of recessed portions of the support ring.
11. A blowing device comprising the cross flow fan according to any one of claim 1 to
claim 10.
12. A refrigeration cycle device comprising: the cross flow fan according to any one of
claim 1 to claim 10; and
a heat exchanger configured to perform heat exchange between an air flow generated
by the cross flow fan and a refrigerant.