JPWO2016071948A1 - Outdoor unit for propeller fan, propeller fan device and air conditioner - Google Patents

Abstract

The propeller fan 1 includes a boss 1a and a wing 2 fixed to the boss 1a. The wing 2 has a shape in which a part of the front edge 21 protrudes toward the pressure surface 2a, or a rear edge 22. Is at least one of the shapes protruding toward the suction surface 2b, and the radial center 28 of the protrusion is half the blade radius Rt from the rotation center line RC. It is located on the outer side in the radial direction with respect to the radial position, and a more uniform blown wind speed distribution can be realized over the radial direction of the blade 2, and noise reduction can be promoted.

Description

  The present invention relates to a propeller fan, a propeller fan device, and an outdoor unit for an air conditioner.

  As a conventional propeller fan shape, the propeller fan shape disclosed in Patent Document 1 can be exemplified. In this propeller fan, the blade attachment angle β gradually decreases from the blade root portion to the blade intermediate portion, and the blade attachment angle β increases from the blade intermediate portion to the blade tip portion. This is because by increasing the blade mounting angle β at the blade tip and increasing the axial flow velocity at the blade tip, air disturbance at the tip is improved and noise is reduced. The reason why the blade attachment angle β at the blade root portion is increased is to increase the air volume.

Patent No. 2590514 (FIG. 9 on page 7)

  In the technique disclosed in Patent Document 1, since the wind speed distribution downstream of the fan cannot be made uniform, a region where the wind speed is locally high is formed, and noise increases when there is a structure such as a grill downstream of the fan. There was a problem to do.

  The present invention has been made to solve such a problem, and an object thereof is to provide a low-noise propeller fan.

In order to achieve the above-described object, the propeller fan of the present invention includes a boss and a wing fixed to the boss, and the wing has a shape in which a part of a leading edge protrudes toward the pressure surface side. Alternatively, a part of the trailing edge has a shape protruding to the suction surface side, and the radial center of the protrusion is radially outward from the radial position half the blade radius from the rotation center line. positioned.
In order to achieve the above object, a propeller fan device of the present invention includes the above-described propeller fan of the present invention, a bell mouth, and a fan grille, and the bell mouth is viewed from above in a blowing direction of the propeller fan. The portion on the upstream side in the blowing direction of the propeller fan is outside the bell mouth in plan view, and the fan grill is arranged downstream in the blowing direction of the propeller fan. Has been.
Furthermore, the outdoor unit for an air conditioner of the present invention for achieving the same object is equipped with the above-described propeller fan of the present invention.

  According to the present invention, a low-noise propeller fan can be provided.

It is a front view of the outdoor unit for air conditioning apparatuses of Embodiment 1 of this invention. It is a figure which shows in plan the internal structure of the outdoor unit for air conditioning apparatuses of Embodiment 1 of this invention. It is a perspective view of the propeller fan of Embodiment 1 of this invention. It is a figure which shows the blowing wind speed distribution of the propeller fan of a comparative example. It is a figure which shows the blowing wind speed distribution of the propeller fan of this invention. It is a graph which shows the blowing wind speed distribution of the propeller fan of this invention. It is a figure which shows the propeller fan and its peripheral part planarly regarding Embodiment 2 and 3 of this invention. It is a perspective view of the propeller fan of Embodiment 4 of this invention. It is a graph of the maximum value of L / Rt of the propeller fan of Embodiment 4 of this invention, and a normalization wind speed.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Note that in the drawings, the same reference numerals indicate the same or corresponding parts as common throughout the specification and the drawings. Moreover, the code | symbol regarding the wing | blade which has multiple sheets shall be attached | subjected only to one representative sheet.

Embodiment 1 FIG.
FIG. 1 is a front view of an outdoor unit for an air-conditioning apparatus according to Embodiment 1 of the present invention. FIG. 2 is a plan view showing the internal configuration of the outdoor unit for an air-conditioning apparatus according to Embodiment 1 of the present invention. FIG. 3 is a perspective view of the propeller fan according to the first embodiment of the present invention.

  As shown in FIGS. 1 to 3, the air conditioner outdoor unit 100 includes a case 51. The case 51 is configured as a housing having a pair of left and right side surfaces 51a and 51c, a front surface 51b, a back surface 51d, an upper surface 51e, and a bottom surface 51f. The side surface 51a and the back surface 51d have openings for sucking air from the outside (see arrow A). Further, in the front surface 51b, an air outlet is formed as an opening for blowing air to the outside (see arrow A). The air outlet is covered with a lattice-shaped fan grill 4.

  Propeller fan 1, fan motor (drive source) 61, bell mouth 3, and heat exchanger 68 are accommodated in case 51 of air conditioner outdoor unit 100. The propeller fan 1, which is an example, is connected to a fan motor 61 disposed on the back surface 51 d side of the propeller fan 1, and is rotated by the driving force of the fan motor 61.

  The heat exchanger 68 is disposed in the vicinity of the side surface 51a and the back surface 51d, and extends in a substantially L shape in plan view along the side surface 51a and the back surface 51d.

  A bell mouth 3 is disposed outside the propeller fan 1 in the radial direction. The bell mouth 3 has a loop shape (ring shape) along the rotation direction of the propeller fan 1.

  2 and 3 exemplify the flow of air, it is merely an illustration for explanation and does not accurately indicate the actual flow.

  The propeller fan 1 includes a boss 1 a and a plurality of wings 2. As an example, in the first embodiment, the propeller fan 1 includes three blades 2.

  The boss 1 a occupies the central portion of the propeller fan 1. In other words, the rotation center line RC of the propeller fan 1 passes through the boss 1a. Although the shape of the boss | hub 1a is not specifically limited, For example, it can comprise in a column shape or a cone shape.

  Each of the three wings 2 is fixed to the outer peripheral surface of the boss 1a. The wing 2 is partially surrounded by the bell mouth 3 in plan view. That is, the downstream portion of each wing 2 is in a region inside the bell mouth 3 surrounded by the bell mouth 3 in plan view, and the upstream portion of each wing 2 is in plan view, It is outside the area inside the bell mouth 3 surrounded by the bell mouth 3. That is, the upstream portion of each wing 2 is located upstream from the upstream end (inlet end) of the bell mouth 3. The fan grill 4 is disposed downstream of the propeller fan 1.

  Although it does not specifically limit as this invention, In this Embodiment 1, since the three wing | blades 2 have the same shape, the one wing | blade 2 is demonstrated below. In the blade of the present invention, a part of the leading edge 21 protrudes toward the positive pressure surface 2a or a part of the trailing edge 22 between the radially inner peripheral end 23 and the outer peripheral end 24. However, it has at least one shape of the shape which protrudes to the suction surface 2b side. In other words, the wing 2 has a shape in which the leading edge 21 protrudes locally toward the pressure surface 2a from the radially innermost periphery to the outermost periphery, or locally, the rear. The edge 22 has at least one of the shapes protruding toward the suction surface 2b. The blade 2 in the illustrated example has both a shape in which a part of the front edge 21 protrudes toward the pressure surface 2a and a shape in which a part of the rear edge 22 protrudes toward the suction surface 2b. Have. Moreover, according to another description aspect, with respect to the blowing direction seen in the direction in which the rotation center line RC extends (the direction illustrated by arrow A in FIG. 3), a part of the protrusion of the front edge 21 described above is downstream in the blowing direction. It is a protrusion to the side, and a part of the protrusion of the rear edge 22 described above is a protrusion to the upstream side in the blowing direction.

  As shown in FIG. 5 to be described later, when the radius from the rotation center line RC to the outer peripheral end 24 of the blade 2 is the blade radius Rt, the radial center 28 of the protrusion of the leading edge 21 and the protrusion diameter of the trailing edge 22 are used. The direction center 28 is located radially outward from the radial position of 0.5 Rt from the rotation center line RC, that is, from the rotation center line RC to a radial direction that is half the radial position of the blade radius. Located on the outside. In addition, the radial center 28 of the protrusion of the front edge 21 and the radial center 28 of the protrusion of the rear edge 22 are the start radius position (the innermost position in the radial direction of the protrusion) 26 and the end radius of the protrusion. The position in the center in the radial direction between the position (the outermost position in the radial direction in the protrusion) 27 is indicated.

  Further, the partial front edge side protruding area 31 starting from the protrusion of the part 21a of the front edge 21 and the partial rear edge side protruding area 32 starting from the protrusion of the part 22a of the rear edge 22 described above are both , Extending in the front-rear direction of the rotation trajectory.

  Further, the protruding height of the partial leading edge side protruding area 31 starting from the protruding portion 21 a of the leading edge 21 is maximum at the leading edge 21 and gradually decreases toward the trailing edge 22. Similarly, the protruding height of the partial trailing edge side protruding area 32 starting from the protruding portion 22 a of the trailing edge 22 is maximum at the trailing edge 22 and gradually decreases toward the leading edge 21. That is, the partial front edge side protruding area 31 starting from the protrusion of the part 21a of the front edge 21 disappears on the pressure surface 2a without reaching the rear edge 22, and from the protrusion of the part 22a of the rear edge 22 The partial trailing edge side protruding area 32 that starts is disappeared without reaching the leading edge 21 on the suction surface 2b.

  Further, the rotation center line RC at a radial position passing through a partial leading edge side protruding area 31 starting from the protrusion of the part 21a of the leading edge 21 and a partial trailing edge side protruding area 32 starting from the protrusion of the part 22a of the trailing edge 22. On the virtual plane obtained by further expanding the arcuate section cut along the arcuate section line V centered on the plane into a plane, the curve of the blade surface connecting the leading edge 21 (21a) to the trailing edge 22 (22a) is approximately It has an arc shape.

  The effect obtained by the above configuration will be described with reference to FIGS. FIG. 4 is a diagram showing a blown wind speed distribution of the propeller fan of the comparative example. FIG. 5 is a diagram showing the blown air velocity distribution of the propeller fan of the present invention. FIG. 6 is a graph showing the blown wind speed distribution of the propeller fan of the present invention.

  As a comparative example, as shown in FIG. 4, the blowout wind speed distribution of the propeller fan provided with only the blade 2 ′ having neither the leading edge side protruding area 31 nor the trailing edge side protruding area 32 is the outer peripheral end of the blade 2 ′. The wind speed distribution is maximized in the vicinity of 24. The reason why the wind speed gradually increases from the inner peripheral end 23 to the outer peripheral end 24 of the blade 2 is that the movement speed of the blade 2 increases as the outer peripheral side of the blade 2 ′ increases, and the work amount of the blade 2 increases. The wind speed decreases most in the vicinity of the outer peripheral end 24 because there is leakage from the gap between the blade 2 and the bell mouth 3 at the outer peripheral end 24 of the blade 2 ′, and part of the upstream side of the blade 2 in the blowing direction. Because it protrudes from the bellmouth 3, the original work amount is small.

  In the propeller fan of such a comparative example, noise is generated when the blown airflow from the propeller fan passes through the fan grill 4 installed downstream of the propeller fan. In general, the noise when the airflow passes through the fan grill 4 is generated. Increases in proportion to the sixth power of the flow velocity, and if there is a maximum portion in the wind speed distribution from the propeller fan, it becomes a large noise source.

  On the other hand, the blowout wind speed distribution of the propeller fan 1 according to the first embodiment of the present invention is configured as described above, so that the swirl direction in the region where the blowout wind speed distribution from the propeller fan 1 is maximized. By reducing the speed component, the work of the blade 2 can be effectively reduced, and the work of the inner peripheral end 23 of the blade 2 can be relatively increased. For this reason, as shown in FIG. 5, a more uniform blowing wind speed distribution can be realized over the radial direction of the blade 2, and noise generated when passing through the fan grill 4 installed downstream of the propeller fan 1 is reduced. , Propeller fan noise can be reduced.

  Further, as described above, the radial position passing through the partial front edge side protruding area 31 starting from the protrusion of the part 21a of the front edge 21 and the partial rear edge side protruding area 32 starting from the protrusion of the part 22a of the rear edge 22 The blade surface connecting the leading edge 21 (21a) to the trailing edge 22 (22a) on the imaginary plane developed by cutting the arcuate section taken along the section line V extending in an arc shape around the rotation center line RC in FIG. Since the curve of Fig. 2 is almost arc-shaped, the flow smoothly follows the blade surface, which can effectively suppress the generation of vortices that are noise sources, and further reduce the noise of the propeller fan. Is supposed to proceed.

  Further, in FIG. 6, the propeller fan of the comparative example and the propeller fan 1 of the first embodiment of the present invention are compared with each other for the comparison of the blowing wind speed distribution. In the propeller fan of the comparative example, an obvious maximum portion of the wind speed is seen near the radius ratio of 0.8. However, in the propeller fan of Embodiment 1 of the present invention, the wind speed near the radius ratio of 0.8 is the comparative example. The wind speed in the area | region of the inner peripheral side of the blade | wing of radius ratio 0.6 or less is increasing rather than the case of the propeller fan of the comparative example, compared with the case of the propeller fan of a comparative example. That is, in the propeller fan according to the first embodiment of the present invention, the obvious maximum portion of the wind speed as in the case of the propeller fan of the comparative example is not seen, and the wind speed distribution is made more uniform than in the case of the propeller fan of the comparative example. I understand that The radius ratio is the ratio of the radial position on the blade when the blade radius Rt (propeller fan radius) is 1, and the standardized wind speed is the maximum of the blowout wind speed distribution of the propeller fan of the comparative example. The wind speed normalized with a value of 1 is shown.

  As described above, according to the first embodiment, it is possible to provide a low-noise propeller fan and an air conditioner outdoor unit.

Embodiment 2. FIG.
Next, Embodiment 2 of the present invention will be described with reference to FIG. FIG. 7 is a diagram showing a plan view of the propeller fan and its peripheral part according to the second embodiment of the present invention. The second embodiment is the same as the first embodiment described above except for the contents described below.

  As shown in FIG. 7, in the propeller fan according to the second embodiment of the present invention, with respect to the protrusion of the front edge 21 and the protrusion of the rear edge 22, the maximum protrusion radius position 25 is the start radius position 26 of the protrusion and the end radius of the protrusion. It is located on the outer side in the radial direction with respect to the radial position of the radial center 28 of the protrusion, which is the center of the position 27.

  The effect obtained by such a configuration will be described. As shown in FIG. 6, the gradient of the change in the blowing wind speed distribution of the propeller fan 1 is relatively small on the inner peripheral side than the maximum part of the wind speed distribution and relatively large on the outer peripheral side than the maximum part of the wind speed distribution. I understand that. On the other hand, by adopting the configuration as in the second embodiment, the change in the slope of the protrusion of the leading edge 21 and the change in the slope of the protrusion of the trailing edge 22 are better than the slope of the change in wind speed distribution. Therefore, the blowout air velocity distribution from the propeller fan can be made even more uniform, the noise generated when passing through the grill installed downstream of the propeller fan can be reduced, and the propeller fan can be reduced in noise.

Embodiment 3 FIG.
Next, a third embodiment of the present invention will be described with reference to FIGS. FIG. 7 is a diagram showing a plan view of the propeller fan and its peripheral part according to the third embodiment of the present invention. The third embodiment is the same as the first or second embodiment described above except for the contents described below.

  As shown in FIG. 7, in the propeller fan according to the third embodiment of the present invention, as in the second embodiment, with respect to the protrusion of the front edge 21 and the protrusion of the rear edge 22, the maximum protrusion radius position 25 is the start of protrusion. It is located radially outside the radial position of the radial center 28 of the protrusion, which is the center of the radial position 26 and the end radius position 27 of the protrusion.

  In addition to the above, in the propeller fan according to the third embodiment of the present invention, with respect to the protrusion of the front edge 21 and the protrusion of the rear edge 22, the maximum protrusion radius position 25 is provided at a position that substantially coincides with the maximum portion of the blowing wind speed distribution. It has been. That is, in setting the position of the maximum projecting radius position 25, a position where the blowing wind speed distribution is obtained and the maximum of the blowing wind speed distribution is obtained with respect to a wing that is different only in the condition that no projection is provided on either the leading edge or the trailing edge. The maximum projecting radius position 25 is set. Specifically, as described above with reference to FIG. 6, the blowout wind speed distribution of the propeller fan of the comparative example is the maximum portion of the wind speed distribution in the vicinity of the radius ratio 0.8 (the radial position from the rotation center line RC to 0.8 Rt). Therefore, regarding the protrusion of the front edge 21 and the protrusion of the rear edge 22, the maximum protrusion radius position 25 is provided at a radial position of 0.8 Rt from the rotation center line RC.

  According to the above configuration, the following advantages can be obtained. That is, since the wind speed can be reduced most at the maximum projecting radius position 25 relating to the protrusion of the leading edge 21 and the trailing edge 22 of the blade 2, the position where the wind speed is most reduced is determined as the blowout wind speed distribution of the propeller fan 1. Approximately equal to the maximum portion of the propeller fan 1, the distribution of the blowing wind speed of the propeller fan 1 can be made more uniform, and noise generated when passing through the fan grill 4 installed downstream of the propeller fan 1 is reduced. The noise of the fan can be reduced.

Embodiment 4 FIG.
Next, based on FIG. 8 and FIG. 9, Embodiment 4 of this invention is demonstrated. FIG. 8 is a perspective view of the propeller fan according to the fourth embodiment of the present invention. FIG. 9 is a graph of L / Rt and the maximum value of the normalized wind speed of the propeller fan according to the fourth embodiment of the present invention. In addition, this Embodiment 4 shall be the same as that of any one of Embodiment 1-3 mentioned above about the contents other than the description shown below.

  As shown in FIG. 8, in the propeller fan according to the fourth embodiment of the present invention, the protrusion height L at the maximum protrusion radius position 25 with respect to the protrusion of the leading edge 21 and the protrusion of the trailing edge 22 of the blade 2 is L / Rt < It is set to satisfy 0.1.

  The effect obtained by the above configuration will be described with reference to FIG. As shown in FIG. 9, in the range of L / Rt <0.1, the maximum value of the standardized wind speed decreases as L / Rt increases. In the range of L / Rt ≧ 0.1, the standardized wind speed is reduced. It shows the tendency that the maximum value of becomes constant. Here, as described above, when a part of the leading edge 21 protrudes toward the pressure surface 2a or a part of the trailing edge 22 protrudes toward the suction surface 2b, the blade surface of the protruding portion becomes the rotation center line. It will be close to a plane perpendicular to RC (a plane orthogonal), and the relative velocity of the airflow flowing through the blade surface will increase, which may cause noise deterioration. In particular, when L / Rt ≧ 0.1, the maximum value of the standardized wind speed is constant, so that this noise deterioration factor becomes dominant and there is a possibility that a sufficient noise reduction effect may not be exhibited. On the other hand, in the fourth embodiment, since the protrusion is provided so as to satisfy L / Rt <0.1 as described above, such noise deterioration can be avoided, and the propeller fan can be prevented. Further noise reduction can be promoted.

  Although the contents of the present invention have been specifically described with reference to the preferred embodiments, various modifications can be made by those skilled in the art based on the basic technical idea and teachings of the present invention. It is self-explanatory.

  In embodiment mentioned above, although the propeller fan was demonstrated as an aspect integrated in the outdoor unit for air conditioning apparatuses, the propeller fan of this invention is not limited to this. The present invention can be implemented as a propeller fan device including the above-described propeller fan, bell mouth, and fan grill. The bell mouth surrounds the downstream portion of the propeller fan in the air flow direction in plan view, and the upstream portion of the propeller fan in the air blow direction is outside the bell mouth in plan view, and the fan grille It is arrange | positioned downstream of the ventilation direction of the propeller fan. And one of the aspects which implemented such a propeller fan apparatus in combination with the heat exchanger is embodiment as an outdoor unit for air conditioning apparatuses demonstrated previously. Therefore, to give another example, the propeller fan device of the present invention is a refrigeration cycle device other than an air conditioner such as a refrigeration device (a device having a refrigeration circuit including at least a compressor, a condenser, an expansion device, and an evaporator). Furthermore, it is also possible to implement as a ventilator, a blower, or a dryer that does not require the provision of a heat exchange element.

  Further, as the best mode for carrying out the present invention, in the example described above, the case where the number of blades is three is illustrated, but the present invention has a configuration with the number of blades other than three. It is also possible to implement, and even in such a configuration, the above-described excellent operational effects can be obtained.

  In the above-described embodiment, the wing has both a shape in which a part of the leading edge protrudes to the pressure surface side and a shape in which a part of the trailing edge protrudes to the suction surface side. However, this aspect is merely an example of the present invention, and the wing relating to the present invention may have the above-described protrusion at the leading edge, but may not have the above-mentioned protrusion at the trailing edge. Alternatively, the wing according to the present invention may have a configuration in which the above-described protrusion is provided on the rear edge while the above-described protrusion is not provided on the front edge.

  1 Propeller fan, 1a boss, 2 blades, 2a positive pressure surface, 2b negative pressure surface, 3 bell mouth, 4 fan grille, 21 front edge, 22 rear edge, 24 outer peripheral edge, 25 maximum protrusion radius position, 28 radial direction of protrusion Center, 100 outdoor unit for air conditioner.

Claims (6)

With the boss,
A wing fixed to the boss,
The wing has a shape in which a part of the leading edge protrudes to the pressure surface side or a part of the trailing edge protrudes to the suction surface side,
The radial center of the protrusion is located on the radially outer side than the radial position of half the blade radius from the rotation center line,
Propeller fan. The maximum protrusion radial position of the protrusion is located on the outer side in the radial direction than the radial position of the center in the radial direction of the protrusion.
The propeller fan according to claim 1. The maximum protruding radius position is provided at a position that coincides with the maximum portion of the blowing wind speed distribution.
The propeller fan according to claim 2. When the radius from the rotation center line to the outer peripheral edge of the blade is the blade radius Rt,
The protrusion height L at the maximum protrusion radius position of the protrusion is set so as to satisfy L / Rt <0.1.
The propeller fan according to any one of claims 1 to 3. A propeller fan according to any one of claims 1 to 4, a bell mouth, and a fan grille,
The bell mouth surrounds a portion on the downstream side in the blowing direction of the propeller fan in plan view,
The portion on the upstream side in the blowing direction of the propeller fan is outside the bell mouth in plan view,
The fan grill is arranged downstream in the blowing direction of the propeller fan.
Propeller fan device. The propeller fan according to any one of claims 1 to 4 is mounted.
Air conditioner outdoor unit.

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