WO2007148645A1

WO2007148645A1 - Outdoor unit for air conditioner

Info

Publication number: WO2007148645A1
Application number: PCT/JP2007/062211
Authority: WO
Inventors: Yoshiki Izumi; Nobuhisa Isemura; Tsutomu Shimizu
Original assignee: Panasonic Corporation
Priority date: 2006-06-19
Filing date: 2007-06-18
Publication date: 2007-12-27
Also published as: CN101331362B; JP2008025983A; JP5003198B2; CN101331362A

Abstract

An outdoor unit (1) for an air conditioner, having improved COP and periodic electric power consumption of the air conditioner, which is achieved by reducing an input to a fan motor of the outdoor unit to enhance static pressure efficiency. The outdoor unit (1) has two propeller fans (5, 6) for promoting heat exchange and rotating in opposite directions to each other, a fan motor (7) for rotating the upwind propeller fan (5) of the two propeller fans, and a reversing mechanism (8) for reversing the rotation direction of the fan motor (7) and transmitting the reversed rotation. The downwind propeller fan (6) is provided coaxial with and on the downstream side of the upwind propeller fan (5) and is reversely rotated by the reversing mechanism (8). The upwind and downwind propeller fans (5, 6) have blade shapes whose chords are bent in the opposite directions and that are line symmetrically formed when viewed from the axis direction. The fans (5, 6) are rotated in the opposite directions from each other but produce airflow in the same direction.

Description

Specification

Air conditioner outdoor unit

Technical field

TECHNICAL FIELD [0001] The present invention relates to a heat exchange accelerating blower used for an outdoor unit of an air conditioner, and more particularly to a technique for improving fan efficiency (static pressure efficiency) of the blower. Background

[0002] This type of air conditioner forms a refrigeration cycle by connecting an indoor unit having a heat exchanger and a blower and an outdoor unit having a compressor, a heat exchanger, and a blower by piping. Air conditioning is performed indoors by cooling operation or heating operation by heat transfer of the refrigerant filled inside. In the outdoor unit, the blower is configured to include a fan and a fan motor to promote heat exchange of the heat exchanger. The air volume of this blower greatly affects the performance of the air conditioner and includes noise. The performance is greatly affected.

[0003] In particular, in heating operation, moisture in the air condenses on the heat exchanger of the outdoor unit and adheres as dew, which interferes with the airflow passing through the heat exchange. At lower temperatures, the dew becomes clogged with ice and frost, so even in such a situation, the fan efficiency of the blower must be improved in order to suppress the decrease in air volume and reduce noise. is important.

[0004] A blower for promoting heat exchange used for an outdoor unit of an air conditioner, and a technology related to a rear stationary blade for the purpose of reducing noise by increasing the efficiency of recovering its dynamic pressure are disclosed ( For example, see JP2002-81695A).

FIG. 19 is a cross-sectional view of an outdoor unit of a conventional air conditioner. The outdoor unit 80 includes a compressor space 83, a heat exchanger 81, a fan motor 82 and a blower 85 for heat exchange promotion, a rear stationary blade 86 for recovering dynamic pressure, and an orifice 87 in a main body outer box 84. 85 and a rear stationary vane 86 that recovers the dynamic pressure are arranged on the same axis of the fan motor 82 as windward force.

Disclosure of the invention

Problems to be solved by the invention However, in the above conventional configuration, the circumferential component V of the absolute speed C of the blower 85

2 Even if Θ is recovered by the rear stationary vane 86, V cannot be recovered by the stationary vane recovery.

Θ

There was a limit to the conversion. That is, the dynamic pressure here is Pd = 0.5 * p * V ² (p:

Θ

The unit is kg 'sec ² ' m ⁴ and the unit of C and V is m / sec). By the way, Φ415ππη

2 Θ

When the rear stationary vane 86 was attached to the blower 85, the improvement of the operating point static pressure efficiency was about 7%.

[0007] The present invention solves the above-described conventional problems, and improves the fan efficiency (static pressure efficiency) of the blower to increase the static pressure and the air volume. The purpose is to provide an outdoor unit for an air conditioner that can suppress noise and reduce noise. Means for solving the problem

[0008] In order to solve the above problems, an outdoor unit of an air conditioner according to the present invention includes a compressor, a heat exchanger, and two propeller fans as fans for promoting heat exchange of the heat exchanger. The two propeller fans are provided close to each other on the same axis, and are configured such that the airflow directions are the same while rotating in the opposite directions (reverse rotation).

[0009] Accordingly, the rotational energy of the wake behind the propeller fan that is on the windward side of the two propeller fans (the energy that is wasted due to the rotational flow) is closely counter-rotated (rotated in the opposite direction to each other). The propeller fan on the leeward side can be recovered, and the rotational flow after the leeward propeller fan can be made almost zero. That is, the operating point static pressure efficiency is improved as compared with the case of using only one propeller fan (the depth is equivalent to two propeller fans of the present invention) for the outdoor unit of the air conditioner. It is possible to increase the static pressure and air flow, or to suppress the decrease of air flow against the air blowing resistance and reduce the noise. As a result, the fan motor input can be reduced, and the COP (Coefficient of performance), period power consumption, and noise of the air conditioner can be reduced.

The invention's effect

[0010] The outdoor unit of the air conditioner of the present invention collects the rotational energy (waste energy associated with the rotational flow) downstream of the windward propeller fan with a counter-rotating leeward propeller fan, and further leeward propeller fan. Since the rotational flow of the wake can be reduced to almost zero, the size of the outdoor unit of the air conditioner is larger than when only one propeller fan is used. The pressure and air volume can be increased, and the operating point static pressure efficiency can be improved. As a result, the fan motor input can be reduced and the COP and period power consumption of the air conditioner can be reduced, or the reduction of the air volume can be suppressed and the noise can be reduced.

[0011] In particular, in heating operation, moisture in the air condenses and adheres as dew to the heat exchanger of the outdoor unit, and dew becomes clogged as ice or frost when the temperature further decreases. The air conditioner is highly efficient and the air flow is reduced and the noise increase [] is suppressed even when the air flow through the heat exchanger is disturbed. An outdoor unit can be provided.

Brief Description of Drawings

FIG. 1 is a cross-sectional view of an outdoor unit of an air conditioner according to Embodiment 1 of the present invention.

FIG. 2 is a plan view in the A direction of the windward propeller fan of the outdoor unit of the air conditioner according to the first embodiment of the present invention.

FIG. 3 is a plan view in the A direction of the leeward propeller fan of the outdoor unit of the air conditioner according to the first embodiment of the present invention.

[Fig. 4] Fig. 4 is a characteristic flow rate characteristic airflow ratio of a propeller fan of an outdoor unit of an air conditioner according to Embodiment 1 of the present invention.

FIG. 5 is a performance diagram showing a developed blade row and a speed triangle of a cylindrical cut surface at a mean square radius position of the wind upper and lower propeller fan of the outdoor unit of the air conditioner according to the first embodiment of the present invention.

[Fig. 6] Fig. 6 is a static pressure / air flow characteristic diagram of a wind upper / lower propeller fan (double reversing fan) of an outdoor unit of an air conditioner according to Embodiment 1 of the present invention.

FIG. 7 is a cross-sectional view of an outdoor unit of an air conditioner according to Embodiment 2 of the present invention.

FIG. 8 is a meridional view of a wind up / down propeller fan of an outdoor unit of an air conditioner according to Embodiment 4 of the present invention.

FIG. 9 is a radial cross-sectional view of a wind up / down propeller fan of an outdoor unit of an air conditioner according to Embodiment 4 of the present invention.

[Fig. 10] Wind up and down side propeller fan of the outdoor unit of the air conditioner according to Embodiment 5 of the present invention. FIG.

FIG. 11 is a radial cross-sectional view of a wind up / down propeller fan of an outdoor unit of an air conditioner according to Embodiment 5 of the present invention.

FIG. 12 is a plan view in the A direction of an upwind mixed flow fan of an outdoor unit of an air conditioner according to Embodiment 6 of the present invention.

FIG. 13 is a plan view in the A direction of the leeward mixed flow fan of the outdoor unit of the air conditioner according to the first embodiment of the present invention.

FIG. 14 is a meridional view of an up-down side mixed flow fan of an outdoor unit of an air conditioner according to Embodiment 6 of the present invention.

FIG. 15 is a meridional view of an up-down side mixed flow fan of an outdoor unit of an air conditioner according to Embodiment 7 of the present invention.

FIG. 16 is a radial cross-sectional view of a wind up / down side mixed flow fan of an outdoor unit of an air conditioner according to Embodiment 7 of the present invention.

FIG. 17 is a meridional view of an up-down mixed flow fan of an outdoor unit of an air conditioner according to Embodiment 8 of the present invention.

FIG. 18 is a radial cross-sectional view of a wind up / down side mixed flow fan of an outdoor unit of an air conditioner according to Embodiment 8 of the present invention.

FIG. 19 is a cross-sectional view of an outdoor unit of an air conditioner according to a conventional example.

BEST MODE FOR CARRYING OUT THE INVENTION

[0013] A first invention includes a compressor, a heat exchanger, and two propeller fans as fans for promoting heat exchange of the heat exchanger, and the two propeller fans are coaxial. They are provided close to each other and are configured so that the airflow directions are the same while rotating (reversely rotating) in opposite directions.

[0014] Thus, the rotational energy behind the propeller fan on the windward side of the two propeller fans (waste energy associated with the rotational flow) is closely counter-rotated (rotated in the opposite direction to each other). The propeller fan on the leeward side can be recovered, and the rotational flow after the leeward propeller fan can be made almost zero. That is, the size of the outdoor unit of the air conditioner is large, and the depth of one propeller fan (the depth is the same as the two propeller fans of the present invention) Compared to the case of using only the operating point, the static pressure efficiency at the operating point can be improved, and the static pressure and the air volume are increased, or the decrease in the air volume due to the blowing resistance such as dew and frost attached to the heat exchanger is suppressed. In addition, noise can be reduced. As a result, the fan motor input can be reduced and the COP, period power consumption, and noise of the air conditioner can be reduced.

[0015] The second aspect of the invention is the outdoor unit of the air conditioner of the first aspect of the invention, in particular, the two propellers are each of which the wing shape is a chord shape and the bending direction is opposite, In other words, the plane shape of one propeller fan is the same or similar when reversed. As a result, only the hub is changed as the shape, and the design for demonstrating the performance as a double reversing fan becomes easy.

[0016] The third invention is a propeller fan, particularly in the outdoor unit of the air conditioner of the first or second invention, wherein one fan motor and a reversing mechanism for reversing the rotation direction of the fan motor are transmitted. Of the two propeller fans, one propeller fan is driven by the fan motor, and the other propeller fan is driven by the reversing mechanism.

[0017] With this, it is possible to drive two propeller fans to rotate in opposite directions with one fan motor, and since there is one heavy fan motor, the air conditioner's It can be produced at low cost and light weight with fewer components of the outdoor unit.

[0018] The fourth aspect of the invention is, in particular, in the outdoor unit of the air conditioner of the third aspect of the invention, in order of the windward force, the heat exchanger, the fan motor, the windward propeller fan, the reversing mechanism, and the leeward propeller fan. The leeward propeller fan is driven by the fan motor, and the leeward propeller fan is driven by the reversing mechanism.

[0019] With the above configuration, two propeller fans can be arranged as far as possible from the heat exchanger, and a large space can be formed between the heat exchanger ^^ and the propeller fan. It is possible to further promote heat exchange by making the wind speed distribution of the vessel uniform. In addition, there is no wind noise due to the interaction between the heat exchanger and the windward propeller fan. Furthermore, since there is no fan motor downstream of the leeward side blower fan fan, the draft resistance can be reduced.

[0020] In a fifth aspect, the reversing mechanism of the third or fourth aspect is provided in the hub of the windward propeller fan. Or in the hub of the leeward propeller fan, or in the hubs of both the leeward and leeward propeller fans, the two propeller fans can be configured closer together.

[0021] The sixth invention is such that, in the first or second invention, two fan motors are provided in each of the two propeller fans, and the two propeller fans are driven by the fan motors provided respectively. As a result, the rotation speed of the two propeller fans can be adjusted individually, and any setting can be made according to the operating conditions.

[0022] In a seventh invention according to the third to sixth inventions, since the fan motor is an outer rotor type, the fan motor is configured inside the hub of the propeller fan, so that the fan motor is provided. Since no space is required, it is possible to more effectively use the space that becomes the air path of the outdoor unit, and it is possible to make the air velocity distribution of the heat exchanger ^ uniform and improve noise reduction. In addition, the outdoor unit can be downsized.

[0023] In an eighth invention according to the first to seventh inventions, the rotational speed of each of the two counter-rotating propeller fans (co-rotating fan) on the same axis is changed. By changing the rotation speed of the two propeller fans that rotate, the speed triangles of the individual propeller fans differ, and the timing of the work time of the individual propeller fan blades shifts. Even if the time axis of work is taken, the peak of discrete noise due to harmonics that do not interfere with each other can be generated, and low noise can be achieved.

[0024] The ninth invention is the ratio of the chord length L at the mean square radial position of the blade of the propeller fan to the representative actual length b in the radial direction of the blade in the first to eighth inventions. The aspect ratio bZL is bZ L≤l. 1, and the outer peripheral chord length of the propeller fan is greater than or equal to the hub chord length.

[0025] Since the outer chord length of each propeller fan is configured to be longer than the hub chord length, securing a large blade area at the blade tip sufficiently absorbs the aerodynamic load and performs work. Therefore, the fan efficiency of each propeller fan itself is improved and the noise is reduced. Furthermore, if the aspect ratio is set to bZL≤l. 1, the air volume per noise can be increased.

[0026] In a tenth aspect based on the first to ninth aspects, the two counter-rotating propellers (double reversing fans) that are coaxially rotated counterclockwise are the leading edges on the meridional plane (meridional plane). Upwind Concave with respect to the side, blade cross-sectional shape with a radial cross section is concave with respect to the windward side, and the outer chord length of each propeller fan is configured to be longer than the nose chord length.

[0027] With the above configuration, the rotational energy of the wake of the windward propeller fan (waste energy associated with the rotational flow) is recovered by the counter-rotating leeward propeller fan, and further the rotational flow of the wake of the leeward propeller fan. The static pressure and air volume can be increased compared to the case of using only a large size propeller fan and an air conditioner outdoor unit. Efficiency can be improved. Furthermore, the suction surface force of the two counter-rotating propeller fans on the same axis causes the tip vortex generated near the tip side of the suction surface of the propeller fan to be The concave part on the windward side of the blade cross-section of the directional cross section promotes the generation of the tip vortex and optimizes the flow state of the blades of each propeller fan. Can be improved. Also, since the outer chord length of each propeller fan fan is longer than the hub chord length, the blade tip vortex can be strengthened to generate a blade tip vortex quickly and strongly, and it can be quickly broken down. The fan noise and fan efficiency can be improved without interference.

[0028] In an eleventh aspect based on the first to ninth aspects, the two counter-rotating propellers (double reversing fans) that are coaxially rotated counterclockwise have a leading edge on the meridian plane (rotary projection). On the other hand, the tip side is concave from the midpoint of the wing, the hub side is convex, the cross-sectional shape of the wing in the radial cross section is concave to the windward side, and the hub side is convex. Each propeller fan The fan's outer chord length is longer than the hub chord length.

[0029] With the above configuration, the rotational energy of the wake of the windward propeller fan (waste energy associated with the rotational flow) is recovered by the counter-rotating leeward propeller fan, and further the rotational flow of the wake of the leeward propeller fan. The static pressure and air volume can be increased compared to the case of using only a large size propeller fan and an air conditioner outdoor unit. Efficiency can be improved. Furthermore, the suction surface force of the two counter-rotating propeller fans on the same axis causes the tip vortex generated near the tip side of the suction surface of the propeller fan to be The tip side of the blade cross-sectional shape of the directional cross section is concave with respect to the windward side, promoting the generation of this tip vortex Let The hub-side convex part of the blade cross-sectional shape of the above-mentioned radial cross-section attracts the flow that flows in the radial direction of the outer periphery of the blade of the propeller fan, so by promoting the generation of blade vortex and the radial flow, Since the flow state of each propeller fan blade can be optimized most, the operating point static pressure efficiency can be further improved. In addition, since the outer chord length of each propeller fan fan is larger than the hub chord length, the wing tip load can be strengthened to generate wing tip vortices quickly and strongly, and it can be quickly broken down. The fan noise and fan efficiency can be improved without interfering with the wings.

[0030] In a twelfth aspect of the invention according to the first to eleventh aspects of the present invention, a counter flow fan is used instead of a propeller fan instead of two counter-rotating fan (double reversing fan) forces that rotate on the same axis This mixed-flow fan is a mixed-flow fan in which each blade shape is designed to be approximately line-symmetric with respect to the same axial force, and the number of blades is one or more. It is formed in a frustum shape.

[0031] With the above-described configuration, the rotational energy of the wakeward-side mixed fan wake (useless energy associated with the rotational flow) is recovered by the counter-rotating leeward mixed-flow fan, and further after the leeward mixed-flow fan. Since the rotational flow of the air flow can be made almost zero, the static pressure and air volume can be increased compared to the case where only a large-size diagonal flow fan is used in the outdoor unit of the air conditioner. It is possible to improve the operating point static pressure efficiency. Furthermore, the mixed flow fan basically has a higher static pressure than the propeller fan. When a fan with a large fan diameter is used for the outdoor unit of an air conditioner, the static pressure decreases, as is obvious from the similarity force between the fan diameter and the rotational speed of the blower. Therefore, when introducing a fan with a large fan diameter into the outdoor unit of an air conditioner, it is optimal to use a mixed flow fan with high static pressure. This leads to improved operating point static pressure efficiency. In addition, since the chord length on the outer peripheral side of each mixed flow fan fan is larger than the chord length on the hub side, it is possible to increase the load on the wing tip and generate a wing tip vortex quickly and strongly, and to break down quickly. Therefore, fan noise and fan efficiency can be improved without interfering with the rear wing.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

[Embodiment 1] FIG. 1 is a cross-sectional view of an outdoor unit of an air conditioner according to the first embodiment of the present invention. Fig. 2 is a plan view of the windward propeller fan in which the outdoor unit is also viewed in the direction A of Fig. 1. Fig. 3 is a plan view of the leeward propeller fan when the outdoor unit is viewed from the A direction. Figure 4 is an aspect ratio characteristic airflow characteristic chart of each propeller fan, showing the airflow per 41dB noise.

In FIG. 1, an outdoor unit 1 includes a heat exchanger 2, a vertical compressor 3, a soundproof plate 4 that partitions the compressor room and the air passage, an upwind propeller fan 5, a downwind propeller fan 6, and a fan Motor 7 and fan The motor 7 includes a reversing mechanism 8 that houses a gear having a mechanism for reversing the rotation direction of the motor 7, an orifice 9, a front grill 10, and a fan motor base 11. The windward propeller fan 5 and the leeward propeller fan 6 generate a blowing action in the heat exchange 2 and act as a double reversing fan in a fan for promoting heat exchange.

In FIG. 2, the blade 20 of the windward propeller fan 5 has a force of two blades, and is composed of a tip 21, a leading edge 22, a trailing edge 23, and a hub 24 that constitute the outer peripheral edge. An alternate long and short dash line B is a cylindrical cutting line of the blade 20 at the root mean square radius position of the windward propeller fan 5. Then, the chord length L at the mean square radial position of the blade of the prober fan and the representative actual length b in the radial direction of the blade. In FIG. 3, the wing 25 of the leeward propeller fan 6 has two blades and is composed of the tip 26, the leading edge 27, the trailing edge 28, and the hub 29 like the leeward propeller fan 5. The alternate long and short dash line B indicates the cylindrical cutting of the blade 20 at the mean square radius position of the leeward propeller fan 6.

2

Disconnection. The flow of air is based on the fact that it flows in from the leading edges 22 and 27 and flows out from the trailing edges 23 and 28, respectively. The leading edges 22, 27 are moving forward (tilting forward) in the direction of rotation.

[0036] In the windward propeller fan 5 and the leeward propeller fan 6, the shape of each of the blades 20 and 25 is reverse to the chordal shape, and in the three-dimensional coordinate system, each is viewed from the same axial direction. It is designed and formed symmetrically. In other words, the shape of each of the two propeller fans 5 and 6 is the same or similar when the plane shape is reversed, and the blades have the same airflow direction when rotated in opposite directions. It is. As a result, only the pub is changed as the shape, and the design for exhibiting the performance as the double reversing fan becomes easy. Incidentally, when changing the rotation speed of the two propeller fans, the leeward propeller fan 6 is often set to a lower rotation speed than the upwind propeller fan 5. [0037] The number of blades is two in Embodiment 1, but is not particularly limited. As shown in FIGS. 1 to 3, in the first embodiment, the leading edges 22 and 27 are formed by a spiral curve, and the leeward propeller fan 6 has a smaller diameter than the leeward propeller fan 5. However, it is not limited to that. Alternatively, the front edges 22 and 27 may be straight, and a triangular wing (triangular wing) may be attached in close contact with the straight front edge so as to have the same radius on the outer periphery.

[0038] Also, by configuring the outer chord length of each propeller fan to be longer than the hub chord length, it is possible to sufficiently absorb the aerodynamic load by performing a work by ensuring a large blade area at the blade tip, The fan efficiency of each propeller fan itself will be improved and the noise will be reduced. Furthermore, if the aspect ratio is set to bZL≤l. 1, it is possible to increase the air volume per the same noise, as shown in Fig. 4.

[0039] The configuration of the outdoor unit 1 includes a compressor 3, a heat exchanger 2, and two windward propeller fans 5 and a leeward propeller fan 6 that counter-rotate as fans for promoting heat exchange. One fan motor 7 supported by the fan motor base 11 for rotating the windward side propeller fan 5 on the upstream side of the windward side propeller fan 5 and the fan motor 7 coaxially on the downstream side of the windward side propeller fan 5 A reversing mechanism 8 that counter-rotates the rotation direction is provided on the upper side, and a leeward propeller fan 6 that rotates counterclockwise on the same axis as the fan motor 7 is provided on the downstream side of the reversing mechanism 8.

[0040] With this arrangement, two propeller fans 5 and 6 are arranged as far as possible from the heat exchanger 2 to form a larger space between the heat exchanger 2 and the windward propeller fan 5. By doing so, the air velocity distribution of heat exchange 2 can be made uniform, and heat exchange can be further promoted. In particular, when the heat exchange 2 is U-shaped as shown in FIG. 1 or L-shaped (not shown), it is more effective because the wind speed distribution tends to deteriorate. Further, wind noise caused by interference between the heat exchanger 2 and the windward propeller fan 5 can be prevented. Furthermore, since the fan motor 7 and the fan motor base 11 do not exist downstream of the leeward propeller fan 6, it is possible to reduce the ventilation resistance and reduce noise.

[0041] In particular, in heating operation, moisture in the air condenses and adheres to the heat exchanger of the outdoor unit, and dew becomes clogged as ice or frost when the temperature drops further. Even if the situation becomes such that it interferes with the airflow passing through the heat exchanger, the airflow is low. It is possible to provide an outdoor unit of an air conditioner with high efficiency of the blower that suppresses lowering and suppresses noise increase tl.

[0042] The reversing mechanism 8 is installed inside the hub 24 of the leeward propeller fan 5, or inside the hub 29 of the leeward propeller fan 6, or inside the hub 24 of the leeward propeller fan 5, and the leeward propeller fan 6 The hub 29 may be housed in both the hubs 24 and 29, so that the outdoor unit 1 can be further saved in space. At the same time, the fan motor 7 is an outer rotor type fan motor, and the outdoor unit 1 that can be housed in the hub 24 of the leeward propeller fan 5 or in the hub 29 of the leeward propeller fan 6 is further added. Space can be saved. The reversing mechanism 8 and the fan motor 7 can be used in a variety of combinations within the hub of the fan, and space can be saved by making effective use of them.

[0043] With the above configuration, the rotational energy of the leeward propeller fan 5 is recovered by the counter-rotating leeward propeller fan 6 and further rotated by the leeward propeller fan 6 Since the flow can be made almost zero, the static pressure and air volume can be increased compared to the case where the outdoor unit 1 is larger in size and only one propeller fan is used. It is possible to improve the static pressure efficiency. As a result, the input to the fan motor 7 can be reduced, and the COP and period power consumption of the air conditioner can be reduced. Fan motor 7 has a single force Windward propeller fan 5 Backward reversing mechanism 8 Combined with the gear shape and other features, the rotation direction of the shaft of fan motor 7 is set to be the counter-rotating direction to leeward propeller fan 6 Since there are only seven fan motors that can be transmitted and that are heavy, the number of components of the outdoor unit of the air conditioner can be reduced and the weight can be reduced. Since the leading edges 22 and 27 are moving forward, the tip load can be increased, the tip vortex can be generated quickly and strongly, and it can break down quickly without interfering with the rear wing. It becomes possible to improve the performance of fan noise and fan efficiency.

Further, the performance will be described in detail with reference to FIG. Fig. 5 is a performance diagram showing the developed blade row and velocity triangle of the cylindrical cut surface at the mean square radius position of each propeller fan. Deployment of blade 20 Airflow flows at an absolute velocity into the blade row (the blade row that was cut and deployed with the B cylinder in Fig. 2). U is the rotation speed and W is the relative speed. Airflow flows at an absolute speed C into the blade cascade of blade 25 To do. U is the rotational speed (U = U) and W is the relative speed of the exit. Absolute speed C Melide

2 1 2 2 2 Ian flow velocity is C and circumferential component is V. The absolute velocity at the outlet of the deployment blade row 25 is C m2 Θ 3, the rotational velocity is U (U く U), the relative velocity is W, and the Meridian flow velocity is C. Exhibition

3 3 2 3 m3

The circumferential component V is completely recovered in the open blade row 25, and the dynamic pressure Pd is converted to static pressure.

Θ

One tart static pressure increases.

[0045] Pd = 0.5 * p * V ² (ρ is density and unit is kg / sec ² -m ⁴ )

Θ

In this C 1S deployment blade row 25 (blade row cut by B cylinder in Fig. 5), fan motor 7 has m2 2

With more angular torque, the speed is increased to absolute speed C, and the rotational flow component is very small.

Three

Yes. So the Meridian flow velocity c increases and

Since m3 c m2 <c, Meridian flow velocity m3

The air volume q (m ³ Zmin), which is the integration of, increases. Also, here relative speed W> W

1 3 is maintained. Here, the unit of each flow velocity is (mZsec). The rotational flow of the wake C in the deployment blade row 25 is almost zero.

Three

As a result, as shown in FIG. 6 to be described later, the static pressure-air flow characteristics of two counter-rotating propeller fans (double counter-rotating fan) are increased compared to the case of using only one single-stage propeller fan. Will do. Here, suppose that the rotational speed of the windward and leeward propeller fans is set to 550 rpm, and the fan diameter is Φ415 mm. This means that the fan static pressure efficiency of two counter-rotating propeller fans (double reversing fans) is improved. This makes it possible to reduce the COP and period power consumption of the air conditioner.

[0047] Fig. 6 is a characteristic diagram of the static pressure and air flow rate of the double reversing fan of the outdoor unit of the present invention. The characteristic curve of the double reversing fan consisting of two counter-rotating propeller fans and the The characteristic curve of one (single stage) propeller fan is compared. Compared to the case where only one large propeller fan (fan diameter Φ415πιπι) with the same depth as the double reversing fan of the present invention is used for the outdoor unit 1 of the air conditioner, the windward and leeward propellers are used. Experimental data showed that when using fans 5 and 6 (double reversing fan, fan diameter Φ415πιπι), the operating point static pressure efficiency was improved by 18%.

[0048] The diameter of the leeward propeller fan 6 may be smaller than the diameter of the leeward propeller fan 5. In this way, the energy of the rotational flow behind the windward propeller fan 5 can be recovered without waste. Also, the diameter of the leeward propeller fan 6 is equal to the diameter of the leeward propeller fan 5. If the operating speed of the leeward propeller fan 6 is set to be even smaller, the energy of the rotatory flow of the leeward propeller fan 5 can be recovered without waste, and the meridian flow rate can be increased to> C. The air volume increases.

[0049] In addition, since the chord lengths of the tips 21 and 26 on the outer periphery of the windward and leeward propeller fans 5 and 6 are larger than the chord lengths of the hubs 24 and 29 (however, at least the chord lengths of the tips 21 and 26 are Hub 24, 29 up to the same length as the side chord length), the wing tip load is increased, the wing tip vortex is generated quickly and strongly, and it can break down quickly without interfering with the rear wing. As a result, fan noise and fan efficiency can be improved.

[0050] Further, although not shown in the drawing, the leading edges 22, 27 are the force moving forward in the rotational direction. In other cases, the up-and-down propeller fans 5, 6 are axisymmetric, and the leading edges 22, 27 The effect of the double reversing fan can be exerted even when is moving backward in the rotation direction. As long as the wind-up / down-side propeller fans 5 and 6 are at least line-symmetric and the directional relationship of the rotating blade row as shown in Fig. 5 (the bending direction of the blades 20 and 25 is reversed), the leading edge Even if either 22 or 27 can be a combination of forward and reverse in the rotational direction, the effect of the double reversing fan can be exhibited. In addition, the cross-sectional shape of the blade may be either a thin blade or a thick blade having an airfoil shape. However, if the blade is thick, separation can be reduced by controlling the boundary layer of the flow, and lower noise can be realized.

[0051] (Embodiment 2)

FIG. 7 is a cross-sectional view of an outdoor unit of an air conditioner according to the second embodiment of the present invention. In FIG. 7, the outdoor unit 1 includes a heat exchanger 2, a vertical compressor 3, a soundproof plate 4 that cuts the compressor room and the air passage, an upwind propeller fan 5, a downwind propeller fan 6, and an upwind propeller fan. The fan motor 7a that drives the fan 5, the fan motor 7b that drives the leeward propeller fan 6, the orifice 9, the front grill 10, and the fan motor bases 11a and l ib. The windward propeller fan 5 and the leeward propeller fan 6 rotate on the same axis half of each other to produce a blowing action in the heat exchanger 2 and act as a heat exchange promoting blower (double reversing fan). The two fan motors 7a and 7b are outer rotor type fan motors, which are embedded in the respective hubs of the windward propeller fan 5 and the leeward propeller fan 6 and are configured integrally with the fan. [0052] These are, in order from the windward side ^^ 2, the windward propeller fan 5 with the outer rotor fan motor 7a built in, and the leeward propeller fan with the other outer rotor fan motor 7b built-in. 6. The front grille 10 and the leeward propeller fan 5 and the leeward propeller fan 6 have a chord-shaped curved direction opposite to each other. As seen from the figure, it is almost line-symmetric and consists of two blades.

[0053] With the above configuration, the rotational energy of the leeward propeller fan 5 wake (wasteful energy associated with the rotational flow) is recovered by the counter-rotating leeward propeller fan 6 and further rotated by the leeward propeller fan 6 wake. Since the flow can be reduced to almost zero, the static pressure and airflow can be increased compared to the case of using only one propeller fan and the size of the outdoor unit 1 of the air conditioner. It is possible to improve the static pressure efficiency. As a result, the input to the fan motors 7a and 7b can be reduced, and the COP and period power consumption of the air conditioner can be reduced. Furthermore, even if two fan motors 7a and 7b are used, the required air volume and static pressure are the same design as when only one large propeller fan is used in the outdoor unit 1 of the air conditioner. The blade load on two individual propeller fans 5 and 6 (also called double reversing fans) can be reduced, and as a result, even if the two fan motors 7a and 7b inputs are combined, the size is large. When only one propeller fan is used, the input can be made lower than when only one fan motor is used.

[0054] Furthermore, the two fan motors 7a and 7b are outer rotor types and are counter-rotating to each other, and are embedded in the hub portion of the two propeller fans 5 and 6, so that the propeller fans 5 and 6 and the outer rotor Since the fan motors 7a and 7b are combined, it is possible to save space for the outdoor unit of the air conditioner. Here, the fan motors 7a and 7b are not limited to the outer rotor type fan motor, and a fan motor that rotates the fan motor shaft can be installed on the same axis outside the up / down propeller fan. As long as there is no problem, it does not matter. Furthermore, the heat exchanger 2 has a configuration in which the windward propeller fan 5 incorporating the outer rotor fan motor 7a from the windward side and the leeward propeller fan 6 incorporating the other outer rotor fan motor 7b are arranged in this order. Arrange the two farthest propeller fans 5 and 6 at the farthest distance between the heat exchanger ^^ 2 and the windward propeller fan 5 Space can be formed, the wind speed distribution of the heat exchanger 2 can be made uniform, and heat exchange can be further promoted. Further, wind noise caused by interference between the heat exchanger 2 and the windward propeller fan 5 can be prevented. Furthermore, since there is no fan motor or fan motor base downstream of the leeward propeller fan 6, it is possible to reduce the ventilation resistance and reduce noise.

[0055] Also, since the outer and outer chord lengths of the individual propeller fans 5 and 6 are larger than the chord lengths of the hub 24 and 29, the wing tip load is increased and the wing tip vortex is generated quickly and strongly. And it is possible to break down quickly and to improve fan noise and fan efficiency without interfering with the rear wing.

[Embodiment 3]

A third embodiment of the present invention will be described with reference to FIGS. The reference numerals and configuration are omitted because they are described in the first and second embodiments.

[0057] Two propeller fans 5 and 6 (2 counter rotating fans) on the same axis are set by changing the rotation speed of the two propeller fans 5 and 6 (double reversing fans). The present invention provides an outdoor unit for an air conditioner equipped with a double reversing fan. For example, in the first embodiment, the ratio of the rotational speed of the windward propeller fan 5 and the rotational speed of the leeward propeller fan 6 can be set by the gear ratio of the reversing mechanism 8 that is a reversing mechanism. In the second embodiment, since the propeller fans 5 and 6 are provided with the fan motors 7a and 7b, the respective rotational speeds can be freely set.

[0058] With the above configuration, the rotation speeds of the two propeller fans 5 and 6 that are counter-rotating can be changed, so that the speed triangles of the individual propeller fans 5 and 6 are different, and the individual propeller fans 5 and 6 have different speed triangles. Since the timing of the blades 20 and 25 is shifted, the peak of discrete noise is generated due to harmonics that do not interfere with each other even if the blades 20 and 25 work along the time axis. It can also be done with low noise. And if the outer peripheral side 21, 26 string length of each propeller fan fan 5, 6 is longer than the hub 24, 29 side chord length, the blade tip load is strengthened and the blade tip vortex is generated quickly and strongly, and Therefore, it is possible to break down quickly and improve fan noise and fan efficiency performance without interfering with the rear wing.

[Embodiment 4]

FIG. 8 shows the propeller of the counter rotating fan of the outdoor unit according to the fourth embodiment of the present invention. It is Ann's meridian view. FIG. 9 is a radial cross-sectional view of the propeller fan shown in FIG. 8, showing the upper side. Individual up-and-down propeller fans are standardized as 30.

8 and 9, the propeller fan 30 includes two blades 31 and includes a leading edge 32, a trailing edge 33, a hub 34, and a tip 35. Two propeller fans 30 (co-rotating fan) that rotate counterclockwise on the same axis have a leading edge 32 on the meridian plane (rotational projection) that is concave with respect to the windward side, and each propeller fan 30 is viewed from the airflow direction. The blade 31 cross-sectional shape is concave with respect to the windward side in the radial cross section. An air conditioner outdoor unit provided with these two propeller fans 30 is provided.

[0061] With the above configuration, the rotational energy (waste energy associated with the rotational flow) of the leeward propeller fan 30 is recovered by the counter-rotating leeward propeller fan 30, and further the leeward propeller fan 30 wake Since the rotational flow of the air can be reduced to almost zero, the static pressure and air volume can be increased compared to the case where only one large propeller fan is used in the outdoor unit 1 of the air conditioner. It becomes possible to improve the point static pressure efficiency. In addition, due to leakage from the suction surface to the pressure surface of the two counter-rotating propeller fans 30 on the same axis, the tip vortex generated near the tip side of the suction surface of the propeller fan The above-mentioned concave portion of the radial cross-section blade 31 on the windward side of the cross-sectional shape promotes the generation of the tip vortex and optimizes the flow state of the blade 31 of each propeller fan 30. The pressure efficiency can be further improved. Here, the concave wing shape of the propeller fan 30 can achieve this effect more effectively if it is used for both forces that are effective even if it is used for either one of the fans.

[0062] Also, since the outer chord 35 chord length of each propeller fan 30 is longer than the hub 34 chord length, the tip load is increased, the tip vortex is generated quickly and strongly, and the break down is performed quickly. Therefore, fan noise and fan efficiency can be improved without interfering with the rear wing.

[0063] (Embodiment 5)

FIG. 10 is a meridional view of the propeller fan of the counter rotating fan of the outdoor unit in the fifth embodiment of the present invention. FIG. 11 is a radial sectional view of the propeller fan shown in FIG. Individual up-and-down propeller fans are standardized as 36. In FIG. 10 and FIG. 11, the propeller fan 36 includes two blades 37 and includes a front edge 38, a rear edge 39, a hub 40, and a tip 41. C—C is the midpoint of wing 37. Two propeller fans 36 (double-reversing fan) that rotate counterclockwise on the same axis are the leading edge 38 on the meridian plane (rotational projection). The side of the blade 40 is convex, the side of the hub 40 is convex, and the cross section of the blade 37 in the radial cross section is concave on the tip 41 side with respect to the windward side, and the hub 40 side is convex. An air conditioner outdoor unit provided with these two propeller fans 36 is provided.

[0065] With the above configuration, the rotational energy (waste energy associated with the rotational flow) of the leeward propeller fan 36 is recovered by the counter-rotating leeward propeller fan 36, and further the leeward propeller fan 36 wake Since the rotational flow of the air can be made almost zero, the static pressure and air volume can be increased compared to the case where only one large propeller fan is used in the outdoor unit 1 of the air conditioner. It becomes possible to improve the point static pressure efficiency. Furthermore, due to leakage from the suction surface to the pressure surface of the two propeller fans 36 rotating on the same axis, the tip vortex generated near the tip side of the suction surface of the propeller fan 36 The tip of the tip 41 side of the blade 37 in the radial cross-section is concave with respect to the windward side, which promotes the generation of the tip vortex. Blades with the above-mentioned radial cross-section 36 Hub with cross-sectional shape 40 side The convex part attracts the flow flowing radially from the outer peripheral side of the blade 37 of the propeller fan 36. By facilitating the flow, the flow state of the blades 37 of the individual propeller fans 36 can be most optimized, so that the operating point static pressure efficiency can be further improved. Here, the concave and convex wing shape of the propeller fan 36 is effective even if it is used for either one of the fans, but the effect can be exhibited more when it is used for both.

[0066] Also, since the outer chord length 41 string length of each propeller fan 36 is larger than the hub chord length of the hub 40, the load on the blade tip is strengthened so that the blade tip vortex is generated quickly and strongly, and the break down is fast. Therefore, fan noise and fan efficiency can be improved without interfering with the rear wing.

[Embodiment 6]

FIG. 12 is a plan view in the A direction of the upwind mixed flow fan of the outdoor unit according to the sixth embodiment of the present invention, FIG. 13 is a plan view in the A direction of the downwind mixed flow fan, and FIG. Child FIG. Individual wind up and down propeller fans are unified as 42.

In FIG. 12, the upwind mixed flow fan 42 includes two blades 43, a leading edge 44, a trailing edge 45, a tip 46, and a hub 47 that have advanced in the rotational direction. In FIG. 13, the leeward mixed flow fan is composed of two blades 49, a leading edge 50, a trailing edge 51, a tip 52, and a hub 53 that have advanced in the rotational direction. Two counter-rotating fan forces on the same axis are used to promote heat exchange, not a propeller fan, but a mixed-flow fan. Each blade 43, 49 has a chord-shaped curved direction, and the three-dimensional coordinate system The mixed flow fans 42 and 48 (double-reversing fan) are designed to be nearly line-symmetric with respect to the same axial force, and the number of blades 47 and 53 of the mixed flow fans 42 and 48 is It is formed in a substantially frustum shape. The present invention provides an air conditioner outdoor unit equipped with the two mixed flow fans 42 and 48. Here, the windward mixed flow fan 42 rotates faster than the leeward mixed flow fan 48. Leading edges 44 and 50 are advanced in the direction of rotation. This leading edge 44, 50 is a force composed of a spiral curve. The trailing edge 45, 51 is a straight line, and a triangular wing (triangular wing) is attached to the outer circumference side in close contact with the straight leading edge. The radii of the blades 43 and 49 may be configured to be the same.

[0069] With the above configuration, the rotational energy of the wakeward mixed flow fan 42 wake (waste energy associated with the rotational flow) is recovered by the counterclockwise leeward mixed flow fan 48, and further, the leeward mixed flow fan 48 Since the rotational flow of the wake can be made almost zero, the static pressure and the air volume are increased compared to the case where only one fan with mixed flow is used for the air conditioner outdoor unit 1. It is possible to improve the operating point static pressure efficiency. Furthermore, the mixed flow fan basically has a higher static pressure than the propeller fan. When a fan with a large fan diameter is used for the outdoor unit 1 of the air conditioner, the static pressure decreases, as is obvious from the similarity force between the fan diameter and the rotational speed of the blower. Therefore, when a fan with a large fan diameter is inserted into the outdoor unit 1 of the air conditioner, it is optimal to use a mixed flow fan with a high static pressure. This leads to improved operating point static pressure efficiency. The leading edges 44 and 50 are advanced in the direction of rotation, so the tip load can be increased and a stronger tip vortex can be generated. If the tip vortex is generated quickly and strongly, and it breaks down quickly, it will not interfere with the rear wing, and fan noise and fan efficiency will be good.

[0070] Also, the outer side 46, 52 chord length of each mixed flow fan 42, 48 is larger than the hub 47, 53 chord length (However, at least the outer 46,52 chord length is the same length as the hub 47,53 chord length), the wing tip load is increased and the wing tip vortex is generated quickly and strongly. It is possible to break down, and it is possible to improve fan noise and fan efficiency without interfering with the rear wing.

[0071] Further, although not shown in the drawing, the leading edges 44 and 50 are forces that advance in the rotational direction. In other cases, the up-and-down mixed-flow fans 42 and 48 maintain point symmetry and the leading edges 44 , 50 can exert the effect of the double reversing fan even if it moves backward in the rotation direction. In addition, the wind-upward and lower-side mixed flow fans 42 and 48 are not at least line-symmetrical, and the directional relationship of the rotating blade row as shown in Fig. 5 (if Fig. 5 is diverted, the bending direction of blades 20 and 25 is reversed) As long as it is maintained, either the front edge 44 or 50 of the up-and-down side mixed flow fan 42 or 48 can be a combination of forward and reverse with respect to the rotation direction. I can do it.

[Embodiment 7]

A seventh embodiment of the present invention will be described with reference to FIG. 15 and FIG. FIG. 15 is a meridional view of each counter flow fan of the counter rotating fan of the present invention, and FIG. 16 is a radial sectional view of each counter flow fan of the counter rotating fan of the present invention. Individual wind-upper propeller fans are standardized as symbol 60.

In FIG. 15, the blade 61 of the up-and-down side mixed flow fan 60 includes a leading edge 62, a trailing edge 63, a tip 64, and a hub 65. D—D is the midpoint of wing 61. The two counter-rotating fans on the same axis that promote rotation are not propeller fans but mixed-flow fans 60 (double reversing fans). They are designed almost symmetrically with the same axial force and have 2 blades. The mixed flow fan 60 is a mixed flow fan 60, and the hub shape 65 of the mixed flow fan 60 is formed in a substantially truncated cone shape, and the leading edge 62 on the meridian surface (rotational projection) of the mixed flow fan 60 is a blade against the windward side. From the middle point (D-D), the tip 64 side is concave, the hub 65 side is convex, and in the radial cross section, the blade 61 cross section is concave on the tip 64 side with respect to the windward side, and the hub 65 side is It constitutes an air conditioner with two convex fans 60 that are convex.

[0074] With the above-described configuration, the rotational energy of the downstream of the upwind mixed-flow fan 60 (waste energy associated with the rotational flow) is recovered by the counter-rotating leeward mixed flow fan 60, and further, the downwind mixed flow fan 60 Since the rotational flow of the wake can be made almost zero, the outdoor unit 1 of the air conditioner Larger size 静 Static pressure and air volume can be increased compared to the case of using only one mixed flow fan, and the operating point static pressure efficiency can be improved. Furthermore, the mixed flow fan basically has a higher static pressure than the propeller fan. When a fan with a large fan diameter is used for the outdoor unit 1 of the air conditioner, the static pressure decreases, as is obvious from the similar law of the fan diameter and rotation speed of the blower. Therefore, when a fan with a large fan diameter is inserted into the outdoor unit 1 of the air conditioner, the power of using a mixed flow fan with a high static pressure is optimal. This will improve the operating point static pressure efficiency.

[0075] Further, the suction surface force of the two counter-rotating counter-rotating fans 60 on the same axis is generated near the tip 64 side of the suction surface of the counter-flow fan 60 due to the leakage flowing toward the pressure surface. The tip vortex has a concave portion on the tip 64 side of the wing 61 in the radial cross section with respect to the windward side to promote the generation of the tip vortex. The above-mentioned radial cross-section blade 61 The cross-section of the hub 65 on the side of the cross section attracts the flow force in the radial direction of the blade of the mixed flow fan 60. As a result, the flow state of the blades of each mixed flow fan 60 can be optimized most, and the operating point static pressure efficiency can be further improved. Here, the uneven wing shape of the mixed flow fan 60 can exert this effect more effectively when it is applied to both of the forces that are effective even when applied to either one of the fans.

[0076] In addition, the 64 chord length of the outer peripheral side of each mixed flow fan 60 is larger than the chord length of the hub 65! /, So the load on the wing tip is increased and the wing tip vortex is generated quickly and strongly. It is possible to break down and to improve fan noise and fan efficiency without interfering with the rear wing.

[0077] (Embodiment 8)

An eighth embodiment of the present invention will be described with reference to FIGS. FIG. 17 is a meridional view of an individual mixed flow fan of the counter rotating fan of the present invention, and FIG. 18 is a radial sectional view of an individual counter flow fan of the counter rotating fan of the present invention. Here, the up-and-down mixed-flow fan is unified as 66.

In FIG. 17, the blade 67 of the up-and-down mixed flow fan 66 includes a front edge 68, a rear edge 69, a tip 70, and a knob 71. The two counter-rotating fans on the same axis are not propeller fans but mixed flow fans 66 (double reversing fans). It is a mixed flow fan 66 that is formed in a truncated cone shape and is designed to be nearly line-symmetric when viewed from the same axial direction and has two blades. The leading edge of the mixed flow fan 66 on the meridian plane (rotary projection) An air conditioner outdoor unit 1 having two mixed flow fans 66 in which 68 is concave with respect to the windward side and the cross-sectional shape of the blade 67 is concave with respect to the windward side in the radial cross section It is.

[0079] With the above configuration, the rotational energy (waste energy associated with the rotational flow) of the leeward mixed-flow fan 66 is recovered by the counter-rotating leeward mixed flow fan 66, and further, the leeward mixed flow fan 66 Since the rotational flow of the wake can be made almost zero, the static pressure and the air volume can be increased compared to the case where only a single fan with a large size is used for the outdoor unit 1 of the air conditioner. It is possible to improve the operating point static pressure efficiency. Furthermore, the mixed flow fan basically has a higher static pressure than the propeller fan. When using a fan with a large fan diameter for the outdoor unit 1 of the air conditioner, the static pressure decreases, as is obvious from the similar law of the fan diameter and rotation speed of the blower. Therefore, when a fan with a large fan diameter is inserted into the outdoor unit 1 of the air conditioner, it is optimal to use a mixed flow fan with a high static pressure. This will improve the operating point static pressure efficiency. Furthermore, the suction surface force of the two counter-rotating counter flow fans 66 on the same axis causes the tip vortices generated near the tip side 70 of the suction surface of the mixed flow fan 66 due to leakage leaking toward the pressure surface. Since the concave part of the above-mentioned radial cross section of the blade 67 in the radial cross section promotes the generation of the tip vortex, the flow state of the blade 67 of each mixed flow fan 66 can be optimized. The operating point static pressure efficiency can be further improved. Here, the concave blade shape of the mixed flow fan 66 can achieve this effect more effectively if it is used for both forces that are effective even if it is used for either one of the fans.

[0080] Since the chord length on the outer peripheral side of each mixed flow fan 66 is larger than the chord length on the hub 71 side, the load at the wing tip is strengthened so that the wing tip vortex is generated quickly and strongly, and the breakdown is quickly performed. Therefore, fan noise and fan efficiency can be improved without interfering with the rear wing.

Industrial applicability

[0081] As described above, the outdoor unit of the air conditioner according to the present invention collects the rotational energy (wasteful energy associated with the rotational flow) downstream of the windward propeller fan with the leeward propeller fan that counter-rotates. Furthermore, the rotational flow behind the leeward propeller fan can be made almost zero. Therefore, compared to the case where only one large propeller fan is used for the outdoor unit of the air conditioner, the static pressure and the air volume can be increased, and the operating point static pressure efficiency can be improved. It becomes. As a result, it is possible to reduce the fan motor input and reduce the COP and period power consumption of the air conditioner, or suppress the reduction of the air volume against the blowing resistance and reduce the noise. Applicable to various air conditioners such as packaged air conditioners.

In addition, this double reversing fan can be applied to consumer equipment, which is an industrial product that uses a fan. In other words, it can be deployed as a ventilation fan, fan, computer cooling fan, etc.

Claims

The scope of the claims

[1] A compressor, a heat exchanger, and two propeller fans as fans for promoting heat exchange of the heat exchanger are provided, the two propeller fans being provided close to each other on the same axis and opposite to each other An outdoor unit of an air conditioner characterized in that the airflow direction is the same while rotating in the direction.

[2] The air conditioner according to claim 1, wherein each of the two propeller fans is formed in a symmetric shape when viewed from the same axial center direction, wherein each blade shape has a chordal shape with opposite bending directions. Outdoor unit.

[3] One fan motor and a reversing mechanism for reversing and transmitting the rotation direction of the fan motor are provided coaxially with the propeller fan, and one of the two propeller fans is the fan motor. 3. The outdoor unit for an air conditioner according to claim 1, wherein the other propeller fan is driven by the reversing mechanism.

[4] The heat exchanger, the fan motor, the windward propeller fan, the reversing mechanism, and the leeward propeller fan are arranged in order from the windward side, the windward propeller fan is driven by the fan motor, and the windward side 4. The outdoor unit for an air conditioner according to claim 3, wherein a side propeller fan is configured to be driven by the reversing mechanism.

[5] The reversing mechanism is housed inside the hub of the windward propeller fan, inside the hub of the leeward propeller fan, or inside the hub of both the windward and leeward propeller fans. Or the outdoor unit of the air conditioner of 4.

[6] The air according to claim 1 or 2, wherein two fan motors are provided in each of the two propeller fans, and the two propeller fans are driven by the fan motors provided respectively. Harmonic outdoor unit.

[7] The air conditioner outdoor unit according to any one of claims 3 to 6, wherein the fan motor is an outer rotor type.

[8] The outdoor unit for an air conditioner according to any one of claims 1 to 7, wherein the number of rotations of the two counter-rotating propeller fans on the same axis is changed.

[9] The aspect ratio bZL, which is the ratio of the chord length L at the mean square radial position of the blade of the propeller fan to the representative actual length b in the radial direction of the blade, is bZL≤l. Outer peripheral side The air conditioner outdoor unit according to any one of claims 1 to 8, wherein the chord length is equal to or greater than the hub chord length.

[10] The front edge on the meridian surface of the propeller fan is concave with respect to the windward side, the blade cross-sectional shape is concave with respect to the windward side in the radial section, and the outer chord length of the propeller fan is the hub chord The outdoor unit for an air conditioner according to any one of claims 1 to 9, wherein the outdoor unit is not less than a length.

[11] The leading edge of the propeller fan on the meridian plane is concave on the tip side and near the midpoint of the blade with respect to the windward side, and the hub side is convex. The tip side is concave with respect to the windward side and the hub side is convex, and the outer peripheral side chord length of the propeller fan is equal to or greater than the hub side chord length. The outdoor unit of the air conditioner described.

[12] The mixed flow fan according to any one of claims 1 to 1, characterized in that, instead of using a propeller fan for heat exchange promotion, a mixed flow fan having a substantially circular truncated cone shape is used. The outdoor unit of the air conditioner described in the paragraph.