JP2019196705A - Blower - Google Patents

Abstract

To stabilize an operation of an impeller (30) which has gone through creep deformation after the operation, in a blower including the impeller (30) having a plurality of blades (40a-40d) among which at least 1 piece has a different shape.SOLUTION: A balancer (50) is provided at an impeller (30) which, when the gravity center position of the impeller (30) before creep deformation is defined as a first position (G1) and the gravity center position of the impeller (30) after the creep deformation is defined as a second position (G2), offsets the gravity center position before the creep deformation to a third position (G3) from the first position (G1) into the reverse direction from the direction in which the gravity center position displaces from the first position (G1) to the second position (G2) according to the creep deformation.SELECTED DRAWING: Figure 5

Description

  The present disclosure relates to a blower.

  For example, in an outdoor unit of an air conditioner, there is one in which noise reduction is achieved by using a blower having an impeller having blades arranged at unequal pitches (see, for example, Patent Document 1). In an uneven pitch blower, the circumferential pitch of each blade is generally different, and the shape and thickness of each blade are also different.

JP 2007-032284 A

  The impeller is provided with a balancer (weight) for adjusting the center of gravity to the center of rotation. However, when the impeller creep-deforms due to the aging of the blower, the position of the center of gravity shifts from the initial position. As a result, the impeller may vibrate during operation of the blower, and the operation may not be stable.

  An object of the present disclosure is to stabilize the operation of a creep-deformed impeller.

The first aspect of the present disclosure is:
At least one sheet includes an impeller (30) having a plurality of wings (40a to 40d) having different shapes,
When the impeller (30) has the center of gravity of the impeller (30) before creep deformation as the first position (G1) and the center of gravity of the impeller (30) after creep deformation as the second position (G2). The center of gravity position before the creep deformation is changed to the first position (G1) in the direction (B) opposite to the direction (A) in which the center of gravity position is displaced from the first position (G1) to the second position (G2) with the creep deformation. A balancer (50) for offsetting from the first position to the third position (G3) is provided.

  In the configuration in which the balancer (50) of the first aspect is not provided, the second position (G2), which is the center of gravity position after creep deformation, has a deviation amount from the rotation center of the impeller (30) at the first position (G1) It becomes larger than the deviation amount. In contrast, in the first aspect, the center of gravity of the impeller (30) before creep deformation is offset in the direction (B) opposite to the second position (G2) with respect to the first position (G1). Therefore, the position of the center of gravity after creep deformation becomes a position close to the rotation center between the first position (G1) and the second position (G2).

According to a second aspect of the present disclosure, in the first aspect,
If the displacement amount of the gravity center position before and after the creep deformation is r and the offset amount of the gravity center position is x,
x ≦ r
It is characterized by being.

  In the second aspect, since the offset amount is equal to or less than the displacement amount, the position of the center of gravity after creep deformation is higher than the position of the center of gravity after creep deformation in the configuration without the balancer (50) of the present disclosure. Near the center of rotation.

According to a third aspect of the present disclosure, in the second aspect,
r / 2 <x ≦ r
It is characterized by being.

  In the third mode, since the offset amount in the direction (B) is larger than ½ of the displacement amount in the direction (A), the positions of the center of gravity after creep deformation are the first position (G1) and the second position ( G2) is closer to the center of rotation of the impeller (30) than the midpoint. In addition, since the offset amount is equal to or less than the displacement amount, the center of gravity position after creep deformation is greater than the center of gravity position after creep deformation in the configuration without the balancer (50) of the present disclosure. Close to.

According to a fourth aspect of the present disclosure, in any one of the first to third aspects,
The plurality of blades (40a to 40d) have different thickness dimensions and are arranged at unequal pitches.

  In the fourth aspect, in the impeller (30) in which the thickness dimensions of the plurality of blades (40a to 40d) are different from each other and the blades (40a to 40d) are arranged at unequal pitches, Becomes closer to the center of gravity before creep deformation.

According to a fifth aspect of the present disclosure, in any one of the first to fourth aspects,
The balancer (50) is constituted by portions (52a, 52b) in which the thickness of a part of the impeller (30) is changed with respect to the thickness of the other part.

  In a 5th aspect, the balancer (30) integrated with the impeller (30) comprised by the part (52a, 52b) which changed the thickness of a part of impeller (30) with respect to the thickness of another part ( 50), the position of the center of gravity after creep deformation becomes close to the center of rotation.

Drawing 1 is a front view showing a schematic structure of an air blower concerning an embodiment. FIG. 2 is a plan view of the impeller of the blower of FIG. FIG. 3 is a sectional view of the hub of the impeller. FIG. 4A is a front view of the balancer. FIG. 4B is a side view of the balancer. FIG. 5 is a front view of the impeller. FIG. 6 is a cross-sectional view of a hub according to Modification 1 of the embodiment. FIG. 7 is a cross-sectional view of a hub according to Modification 2 of the embodiment.

  The blower (10) of the embodiment will be described with reference to the drawings.

<overall structure>
The blower (10) is applied to, for example, an outdoor unit of an air conditioner, and is used to blow air to an outdoor heat exchanger in the outdoor unit. This blower (10) is composed of a propeller fan that is an axial blower. As shown in FIG. 1, the blower (10) includes an electric motor (11), a rotating shaft (20) that is rotationally driven by the electric motor (11), and an impeller (30) coupled to the rotating shaft (20). It has.

<Impeller>
As shown in FIGS. 1 and 2, the impeller (30) includes a substantially cylindrical hub (31) and a plurality (four in this embodiment) supported by the outer peripheral surface of the hub (31). And wings (40a to 40d). One hub (31) and four blades (40a to 40d) are integrally formed. The material of the impeller (30) is, for example, a synthetic resin.

<Hub>
As shown in FIG. 3, the hub (31) has an outer cylinder (32), a first end plate (33), a second end plate (34), and a boss portion (35). The outer cylinder (32) is formed in a hollow cylindrical shape. The first end plate (33) is formed integrally with the outer cylinder (32) and closes an opening on one end side (motor (11) side) of the outer cylinder (32) in the axial direction. The second end plate (34) is attached to the other end side in the axial direction of the outer cylinder (32) (the side opposite to the electric motor (11)), and closes the opening on the other end side. The boss part (35) protrudes inward of the hub (31) from the central part of the inner wall of the first end plate (33). The boss portion (35) is formed at the center of the hub (31), and is connected to the rotating shaft (20) of the electric motor (11) serving as the rotation center of the blower (10).

<Wings>
As shown in FIG. 2, the wings (40a to 40d) are arranged so as to protrude outward from the outer peripheral surface of the hub (31). The four blades (40a to 40d) are arranged at a predetermined interval in the circumferential direction of the hub (31). Each wing | blade (40a-40d) becomes a shape which spreads toward the outer side of the radial direction of an impeller (30).

  Each blade (40a to 40d) has a blade center (41a to 41d) at the end in the radial direction of the impeller (30) (that is, the hub (31) side), and the diameter of the impeller (30) The outer end in the direction is the blade tip (42a to 42d). The wing base (41a-41d) of each wing | blade (40a-40d) is joined to the hub (31).

  In each blade (40a to 40d), the front edge in the rotational direction of the impeller (30) is the front edge (43a to 43d), and the rear edge in the rotational direction of the impeller (30) is the trailing edge (44a-44d). The front edge (43a-43d) and the rear edge (44a-44d) of each wing (40a-40d) are the outer periphery of the impeller (30) from the wing base (41a-41d) toward the wing tip (42a-42d). It extends to the side.

  Each wing | blade (40a-40d) inclines with respect to the plane orthogonal to the rotating shaft (20) which is a rotation center of an impeller (30). Each blade (40a to 40d) is configured such that the front surface in the rotation direction of the impeller (30) is a pressure surface, and the rear surface in the rotation direction of the impeller (30) is a suction surface. .

  In the impeller (30) of the present embodiment, the circumferential pitches (θ1, θ2, θ3, θ4) of the blades (40a to 40d) are different from each other. That is, the impeller (30) has a plurality of blades (40a to 40d) arranged at unequal pitches. On the other hand, the blades (40a to 40d) are different in shape and thickness from each other so that the center of gravity of the impeller (30) approaches the rotation shaft (20) of the impeller (30). The specific shape and thickness of each wing (40a-40d) are the shape and size of the hub (31) and each wing (40a-40d), and the circumferential pitch of each wing (40a-40d) ( It is designed according to specific values of each part of the impeller (30) such as θ1, θ2, θ3, θ4), and a required center of gravity position.

  This impeller (30) is different from each other in shape and size of each wing (40a to 40d), and therefore, a general impeller in which a plurality of wings having the same shape (substantially the same shape) are formed. On the other hand, the displacement amount (deformation amount) for each blade (40a to 40d) due to creep deformation after operation for a predetermined period is different from each other. For this reason, the impeller (30) of the present embodiment has a larger shift amount of the center of gravity position after creep deformation than the center of gravity position immediately after manufacture, compared to the impeller formed with a plurality of blades having the same shape. . In other words, even if the balance is maintained before the creep deformation, the balance may be lost after the creep deformation, and the shift amount of the center of gravity may be too large.

<Balancer>
In the impeller (30) in which the shapes of the blades (40a to 40d) are different from each other, as shown in FIG. Assuming that the center of gravity of the impeller (30) after creep deformation is the second position (G2), the center of gravity position is displaced from the first position (G1) to the second position (G2) along with the creep deformation. Only the dimension indicated by r) is displaced in the direction indicated by the arrow (A) on the drawing.

  In this embodiment, the center of gravity of the impeller (30) before creep deformation is changed from the first position (G1) to the third position (in the direction represented by the arrow (B) opposite to the arrow (A) ( A balancer (50) for offsetting to G3) is provided (see Fig. 3). By providing this balancer (50), the center of gravity position is displaced from the third position (G3) to the fourth position (G4) in the direction of the arrow (A) with the creep deformation, but the fourth position (G4 ) With respect to the center (O) is smaller than the shift amount of the second position (G2). That is, the position of the center of gravity of the impeller (30) after creep deformation is closer to the rotational axis (20) than the configuration without the balancer (50). In FIG. 5, the center-of-gravity positions (G1 to G4) are exaggerated in terms of the amount of deviation from the center of rotation in order to clearly represent the difference between the positions.

  As shown in FIG. 3, the hub (31) has a balancer attachment portion (55) for attaching a balancer (50) to a corner formed by the inner surface of the outer cylinder (32) and the first end plate (33). ) Is formed. The balancer mounting portion (55) is a flat plate-like portion extending in the radial direction of the hub (see the phantom line in FIG. 4B).

  The balancer (50) is constituted by a clip-like weight (51) shown in FIGS. 4A and 4B. The weight (51) is formed of an elastic plate, and includes two plate portions (51a, 51b), a connecting portion (51c) between the plate portions (51a, 51b), and one plate portion (51b And a mounting guide portion (51d) formed at the end of the head.

  As shown in FIG. 4B, the distance between the open ends of the plate portions (51a, 51b) is smaller than the thickness dimension of the balancer mounting portion (55). When the balancer (50) is attached to the balancer mounting part (55), the connecting part (51c) is deformed and the balancer mounting part (55) is strongly clamped by the spring force, thereby suppressing the displacement of the balancer (50). Is done. The balancer (50) may be attached to the balancer attachment portion (55) from the upper direction in FIG. 3 (second end plate (34) side), or in the left direction in FIG. 3 (boss portion (35) side). ). The example of FIG. 3 is an example in which the balancer (50) is attached from the boss part (35) side.

<Position of the center of gravity>
Next, the relationship between the displacement amount (r) of the gravity center position before and after the creep deformation of the impeller (30) and the offset amount (x) of the gravity center position before the creep deformation will be described.

  As already described with reference to FIG. 5, in this embodiment, the center of gravity of the impeller (30) before creep deformation (for example, immediately after manufacture) is set to the first position (G1), and the impeller after creep deformation (30 ) Is the second position (G2). The first position (G1) and the second position (G2) are gravity center positions when the balancer (50) is not attached to the impeller (30). As described above, since the displacement of the center of gravity position is large in the impellers (30) having different wing shapes, even if a balancer is provided to balance the center of gravity position before creep deformation, creep After the deformation, the position of the center of gravity deviates from the rotation center, the impeller (30) vibrates, and the operation becomes unstable.

In this embodiment, the position of the center of gravity is displaced from the first position (G1) to the second position (G2) in the displacement direction indicated by the arrow (A) by the dimension represented by the displacement amount (r), while creep deformation The position of the center of gravity of the front impeller (30) is offset from the first position (G1) to the third position (G3) in the direction of the arrow (B) opposite to the arrow (A). Then, the offset amount (x) is set with respect to the displacement amount (r).
r / 2 <x ≦ r
It is set to satisfy the relationship. For the offset amount (x), predict the deformation state for each wing (40a to 40d) after creep deformation, find the displacement amount (r) of the center of gravity before and after creep deformation, and use the above relational expression Calculated. The offset direction (B) is determined in a direction opposite to the displacement direction (A) (a direction opposite to 180 °, or a direction opposite to about 180 °).

-Action and effect of the embodiment-
In the present embodiment, in the blower having the impeller (30) in which a plurality of blades (40a to 40d) having different shapes are arranged at unequal pitches, the gravity center position of the impeller (30) before creep deformation is the first position. (G1) and the center of gravity position of the impeller (30) after creep deformation is the second position (G2), the center of gravity position of the impeller (30) is the first position (G1) due to creep deformation. Balancer (50) that offsets the center of gravity position before creep deformation from the first position (G1) to the third position (G3) in the direction (B) opposite to the direction (A) moving from the first position to the second position (G2) Is provided. The relationship between the displacement amount (r) of the center of gravity before and after the creep deformation and the offset amount (x) of the center of gravity is defined as r / 2 <x ≦ r.

  In a conventional impeller, even if a balancer is provided to align the center of gravity with the center of rotation, if the blower is operated for a predetermined time, the impeller creeps due to secular change and the position of the center of gravity shifts. May vibrate and operation may become unstable.

  In the present embodiment, the balancer (50) is attached, and the offset amount (x) is larger than ½ of the displacement amount (r), so the fourth position (G4) which is the center of gravity position after creep deformation. Is closer to the center of rotation (O) than the midpoint of the first position (G1) and the second position (G2). Further, since the offset amount (x) is equal to or less than the displacement amount (r), the fourth position (G4) is at least closer to the center of rotation (O) than the second position (G2).

  Therefore, when the balancer (50) of this embodiment is provided, the center of gravity position (G4) after creep deformation approaches the center of rotation (O) as compared with the case where the balancer (50) is not provided. Therefore, the impeller (30) of the blower (10) of the present embodiment is kept in a small vibration state even after creep deformation.

  Further, the third position (G3), which is the center of gravity set by the balancer (50) before creep deformation, has an offset amount (x) larger than ½ of the displacement amount (r), so the balancer (50) It is farther from the center of rotation than the first position (G1), which is the center of gravity when not provided. However, the creep deformation, which is the secular change of the shape of the impeller (30), reaches the upper limit of deformation after a certain period (for example, about one year), and no longer deforms. In other words, the creep deformation is completed at an early stage of the product life, so that the blower (10) can be operated with the mass balance improved for most of the subsequent product use periods, and the vibration of the impeller (30) Noise can be suppressed.

-Modification of the embodiment-
<Modification 1>
FIG. 6 is a cross-sectional view of the hub (31) according to the first modification of the embodiment. In this modification, the shape of the balancer mounting portion (55) is different from that in FIG. The balancer mounting portion (55) is the same as in FIG. 3 in that it is a plate-like portion formed on the radial line of the hub (31), but the boss portion ( 3 is different from FIG. 3 in that it is formed up to the outer peripheral surface 35) and the height on the outer cylinder (32) side is higher than the height on the boss portion (35) side. As the balancer (50), the weight (51) shown in FIG. 4 is mounted at a position near the outer cylinder (32) of the balancer mounting portion (55).

  In the first modification, the position of the balancer (50) can be set higher than that in the example of FIG. 3, and thus it is suitable for the impeller (30) having a high center-of-gravity position.

  Other functions and effects are the same as in the above embodiment.

<Modification 2>
FIG. 7 is a cross-sectional view of a hub (31) according to Modification 2 of the embodiment. This modification is an example in which the configuration of the balancer (50) is different from those in FIGS. The balancer (50) of the hub (31) includes a thick wall portion (52a) formed near the first end plate (33) of the outer cylinder (32) and a second end plate ( 34) It is formed by the thin part (52b) formed in the part near. The thick part (52a) and the thin part (52b) are formed in a part of the outer cylinder (32) in the circumferential direction. Note that it is not necessary to form both the thick part (52a) and the thin part (52b). Good. As described above, the balancer (50) may be configured by portions (52a, 52b) in which the thickness of a part of the impeller (30) is changed with respect to the thickness of the other part.

  In the second modification, since the balancer (50) is integral with the impeller (30), the position of the balancer (50) does not shift during the rotation of the impeller (30). Therefore, it can suppress that the set gravity center position shifts during rotation.

  Other functions and effects are the same as in the above embodiment.

<< Other Embodiments >>
About the said embodiment, it is good also as the following structures.

  For example, in the above embodiment, the center of gravity position of the impeller (30) before creep deformation is offset from the first position (G1) to the third position (G3), and the offset amount (x) is calculated as the center of gravity before and after the creep deformation. The position displacement amount (r) is determined so as to satisfy the relationship of r / 2 <x ≦ r, but may satisfy the relationship of x ≦ r.

  Even in this configuration, since the offset amount (x) is equal to or less than the displacement amount (r), the fourth position (G4) is closer to the rotation center (O) than at least the second position (G2). In addition, the offset amount (x) is larger than zero (not a negative value) as can be seen from the relationship between the displacement direction (A) and the offset direction (B), so the center of gravity position after creep deformation The fourth position (G4) is closer to the center of rotation (O) than the midpoint of the second position (G2).

  Therefore, even in this configuration, the center of gravity position (G4) after creep deformation is closer to the center of rotation (O) than the center of gravity position (G4) after creep deformation compared to the case where the balancer (50) is not provided. The vibration of the car (30) is kept small even after creep deformation.

  Further, the creep deformation, which is the secular change of the shape of the impeller (30), is completed at the beginning of the product life, and thereafter, stable operation can be performed as in the above embodiment.

  In the above-described embodiments and modifications, the impeller (30) is provided with a separate weight (51) as the balancer (50), or the thick portion (52a) in which the thickness of a part of the hub (31) is changed. Or a thin wall part (52b) is used as a balancer (50), but the thickness and shape of each wing (40a-40d) can be partially changed, or each wing (40a-40d) The balancer (50) may be configured by attaching a weight of another member to the other.

  In the above-described embodiment, the unequal pitch impeller (30) in which the thickness and shape of each blade (40a to 40d) are different from each other has been described, but at least one impeller (30) has a plurality of different shapes. What is necessary is just to have a wing | blade and it does not necessarily need to be an unequal pitch.

  The number of wings (40a to 40d) is not limited to four, but may be three or any other number.

  The relationship between the arrow (A) and the arrow (B) is not limited to the reverse direction of 180 °, but may be a substantially reverse direction.

  Although the propeller fan which is an axial-flow fan was demonstrated in the said embodiment, the technique of this indication is applicable also to other types of fans, such as a centrifugal fan.

  While the embodiments and the modifications have been described above, various changes in form and details can be made without departing from the spirit and scope of the claims. In addition, the above embodiments and modifications may be appropriately combined or replaced as long as the functions of the subject of the present disclosure are not impaired.

  As described above, the present disclosure is useful for a blower.

10 Blower
30 impeller
31 Hub
40a wing
40b wing
40c wing
40d wing
50 Balancer
G1 1st position
G2 2nd position
G3 3rd position
t1 thickness
T2 thickness

Claims (5)

At least one sheet includes an impeller (30) having a plurality of wings (40a to 40d) having different shapes,
The impeller (30) has a position of the center of gravity of the impeller (30) before creep deformation as the first position (G1) and a position of the center of gravity of the impeller (30) after creep deformation as the second position (G2). The center of gravity position before the creep deformation is changed to the first position (G1) in the direction (B) opposite to the direction (A) in which the center of gravity position is displaced from the first position (G1) to the second position (G2) with the creep deformation. A blower comprising a balancer (50) for offsetting from the first position to the third position (G3). In claim 1,
If the displacement amount of the gravity center position before and after the creep deformation is r and the offset amount of the gravity center position is x,
x ≦ r
A blower characterized by being. In claim 2,
r / 2 <x ≦ r
A blower characterized by being. In any one of Claims 1-3,
The plurality of blades (40a to 40d) have different thickness dimensions and are arranged at unequal pitches. In any one of Claims 1-4,
The said balancer (50) is comprised by the part (52a, 52b) which changed the thickness of a part of impeller (30) with respect to the thickness of another part, The air blower characterized by the above-mentioned.

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