CN206503769U - centrifugal fan - Google Patents

Abstract

A centrifugal fan (4) has an impeller (8) and an outer rotor type motor (7). The outer rotor type motor (7) has: a stator (10); and a cup-shaped rotor (20), which faces the main plate (60) of the impeller (8) and is arranged on the outer peripheral side of the stator (10). In the centrifugal fan (4), a rigid member (90) is disposed with the main board (60) sandwiched between the rotor (20), and a first elastic member is disposed between the main board (60) and the rotor (20). component (50), and a second elastic component (80) is disposed between the main board (60) and the rigid component (90). In this state, the rotor (20), the main board (60) and the rigid component (90) room is fixed.

Description

centrifugal fan

technical field

The utility model relates to a centrifugal fan, in particular to a centrifugal fan which drives an impeller to rotate through an outer rotor type motor.

Background technique

In air conditioners, air cleaners, and the like, suction, supply, and discharge of air may be performed using a centrifugal fan. A centrifugal fan mainly has an impeller and a fan motor that drives the rotation of the impeller. The impeller has a plurality of blades arranged annularly around the axis of rotation, and a main plate connecting the blades together.

Furthermore, as a fan motor of such a centrifugal fan, an outer rotor type motor as disclosed in Patent Document 1 (Japanese Patent Application Laid-Open No. 2005-264882 ) may be used. The outer rotor type motor mainly includes a stator and a cup-shaped rotor, and the rotor is arranged on the outer peripheral side of the stator. In addition, this centrifugal fan has a structure in which the rotor of the fan motor of the outer rotor type is arranged to face the main board of the impeller, and a rubber gasket (elastic member) is arranged between the rotor and the main board, and a screw is screwed to the main board. Insert, so that the main board and the rotor are connected.

In the centrifugal fan using the above-mentioned conventional outer rotor type fan motor, since an elastic member is arranged between the main board and the rotor, due to vibration and impact when transporting an air conditioner equipped with a centrifugal fan, etc., it is easy to cause the main board to oppose. Deformation like rotor tilt. Furthermore, when the amount of deformation of such a main board increases, there is a possibility that the main board may be cracked in the portion where the screw is screwed into the main board and its peripheral portion. In addition, if only the elastic member is disposed between the main plate and the rotor, there is a possibility that noise such as a rattling sound during operation of the centrifugal fan cannot be sufficiently reduced.

In this way, in the centrifugal fan using the above-mentioned conventional outer rotor fan motor, the main plate of the impeller may be damaged during transportation, and the noise during operation may not be sufficiently reduced.

prior art literature

patent documents

Patent Document 1: Japanese Patent Laid-Open No. 2005-264882

Utility model content

An object of the present invention is to prevent damage to the main plate of the impeller during transportation and to sufficiently reduce noise during operation in a centrifugal fan in which the impeller is driven to rotate by an outer rotor type motor.

means to solve the problem

The centrifugal fan of the first aspect has an impeller and an outer rotor type motor. The impeller has a plurality of blades arranged annularly around the axis of rotation, and a main plate connecting the blades together. The outer rotor type motor has a stator and a cup-shaped rotor that faces the main plate and is arranged on the outer peripheral side of the stator. In addition, here, the rigid member is arranged so as to sandwich the main board between the rotor and the first elastic member is arranged between the main board and the rotor, and the second elastic member is arranged between the main board and the rigid member. In the state, the rotor, the main board and the rigid parts are fixed. Here, the rigid member is a member whose rigidity is higher than that of the main board, such as using a metal member when the main board is a resin-made member. The elastic member is a member that is easily elastically deformed such as a rubber member.

Here, the degree of deformation such that the main board is inclined relative to the rotor during transportation can be suppressed by a rigid member disposed so as to sandwich the main board with the rotor. In addition, noise during operation can be reduced by the second elastic member arranged between the main board and the rigid member.

In this way, here, in addition to the first elastic member arranged between the main board and the rotor, a rigid member is arranged so as to sandwich the main board with the rotor, and a second elastic member is arranged between the main board and the rigid member, thereby It is possible to prevent damage to the main plate of the impeller during transportation, and to sufficiently reduce noise during operation.

In the centrifugal fan of the second aspect, according to the centrifugal fan of the first aspect, the rotor, the main board, and the rigid member are fixed by bolts.

Here, if the main plate is deformed such that it is inclined relative to the rotor during transportation, the main plate may be cracked at the portion where the bolt is inserted through the main plate and its peripheral portion. However, here, since the degree of deformation can be suppressed by the rigid member, it is possible to suppress the main board from being cracked.

The centrifugal fan according to the third aspect is the centrifugal fan according to the second aspect, wherein the third elastic member is arranged between the bolt and the main plate.

If the main board is in direct contact with the bolt at the part where the bolt is inserted through the main board, the vibration will be transmitted between the main board and the rotor through the bolt, which may affect the effect of using the first and second elastic members to reduce the noise during operation. to adverse effects.

Therefore, here, as described above, the third elastic member is arranged between the bolt and the main plate to avoid direct contact between the main plate and the bolt.

Accordingly, here, the effect of reducing noise during operation by the first and second elastic members can be sufficiently obtained.

The centrifugal fan of the fourth aspect is the centrifugal fan of the third aspect, wherein the third elastic member is a member integral with the first elastic member or the second elastic member.

Here, since the third elastic member is integrated with the first elastic member or the second elastic member, the number of elastic members can be reduced, thereby improving the assemblability when connecting the main board and the outer rotor type motor.

The centrifugal fan according to the fifth aspect is the centrifugal fan according to any one of the second to fourth aspects, wherein there are three or more bolts arranged in a ring around the rotation axis.

Here, since three or more bolts are arranged in a ring shape around the rotation axis, the outer rotor type motor and the main plate can be reliably centered.

The centrifugal fan according to the sixth aspect is the centrifugal fan according to any one of the second to fourth aspects, wherein the bolt extends from the rotor toward the rigid part side, and the rotor, the main board, and the rigid part are screwed together at the end of the rigid part side from the bolt. It is fixed with a nut.

Here, when the rotor, the main board, and the rigid member are fixed by bolts, since the nut is screwed from the end of the bolt on the rigid member side, the elastic member can be inserted while the bolt is inserted through the elastic member, the main board, and the rigid member. , the main board and the rigid part coincide sequentially with respect to the rotor. In addition, when tightening the rotor, the main plate, and the rigid member, the tightening amount of the nut can also be managed based on the position of the end of the bolt.

Therefore, here, the assemblability when connecting the main board and the outer rotor type motor can be improved, and the tightening amount of the nut including the compression amount of the elastic member that affects the noise reduction effect during operation can be managed, and can be controlled by Bolts hold the rotor, main plate and rigid parts in place.

Description of drawings

FIG. 1 is an external perspective view of an air conditioner employing a centrifugal fan according to an embodiment of the present invention.

Fig. 2 is a schematic side sectional view of the air conditioner.

3 is a cross-sectional view showing the structure of the fan motor and the connection structure between the fan motor and the main plate of the impeller.

Fig. 4 is an exploded perspective view showing the connection structure of the fan motor and the main board.

FIG. 5 is an enlarged view showing the vicinity of stud bolts in FIG. 3 .

Label description

4 centrifugal fans

7 Fan motor (outer rotor type motor)

8 impellers

10 stator

20 rotors

40 studs

45 Nut with washer

50 first elastic member

55 third elastic member

60 motherboard

70 blades

80 Second elastic member

90 rigid parts

detailed description

Next, embodiments of the centrifugal fan of the present invention will be described with reference to the accompanying drawings. In addition, the concrete structure of embodiment of the centrifugal fan of this invention is not limited to the following embodiment, It can change in the range which does not deviate from the summary of this invention.

(1) The overall structure of the air conditioner

FIG. 1 shows an external perspective view of an air conditioner 1 employing a centrifugal fan 4 according to one embodiment of the present invention (the ceiling is omitted). Here, the air conditioner 1 is a ceiling-mounted air conditioner, and mainly includes a casing 2 in which various components are housed, and a decorative panel 3 disposed on the lower side of the casing 2 .

The casing 2 of the air conditioner 1 is a box-shaped member with an open bottom, and as shown in FIG. And, the decorative panel 3 has: a suction port 3a arranged substantially in the center to suck the air of the air-conditioning room into the housing 2; 2 is blown out to the air-conditioning room, and the decorative panel 3 is arranged so as to fit into the opening of the ceiling.

The casing 2 is mainly equipped with: a centrifugal fan 4, which sucks the air in the air-conditioning room into the casing 2 through the suction port 3a of the decorative panel 3 and blows it out to the outer peripheral direction; a heat exchanger 5, which surrounds the outer periphery of the centrifugal fan 4 and the bell mouth 6, which is used to guide the air sucked in from the suction port 3a to the centrifugal fan 4. The centrifugal fan 4 has a fan motor 7 provided substantially at the center of the top plate 2a of the casing 2, and an impeller 8 connected to the fan motor 7 and driven to rotate.

The impeller 8 is a component made of resin, and mainly includes: a disc-shaped main board 60 connected to the fan motor 7; a plurality of blades 70 arranged on the main board 60 and the fan motor in a ring around the rotation axis O of the main board 60; 7 the opposite side; and an annular shroud 75 configured to sandwich the plurality of blades 70 between the shroud 75 and the direction of the rotation axis O of the main plate 60 . The main plate 60 is formed so that a substantially truncated conical hub portion 61 protrudes toward the suction port 3a at its central portion, and connects ends of a plurality of blades 70 on the fan motor 7 side at its outer periphery. The shroud 75 is a bell-shaped member that curves and protrudes toward the suction port 3 a as it goes from the outer peripheral portion toward the central opening, and connects ends of the plurality of blades 70 opposite to the fan motor 7 . Here, the blade 70 is a member in the shape of a turbine blade inclined backward with respect to the rotation direction of the impeller 8 .

In addition, the air conditioner 1 provided with the centrifugal fan 4 is not limited to a ceiling-mounted air conditioner, and other types may be used. In addition, the structure of the fan motor 7 and the connection structure of the fan motor 7 and the main plate 60 of the impeller 8 are demonstrated later.

(2) The structure of the fan motor and the connection structure between the fan motor and the main board of the impeller

Next, the structure of the fan motor 7 and the connection structure of the fan motor 7 and the main plate 60 of the impeller 8 will be described using FIGS. 2 to 5 . Here, FIG. 3 is a sectional view showing the structure of the fan motor 7 and the coupling structure of the fan motor 7 and the main plate 60 of the impeller 8 . FIG. 4 is an exploded perspective view showing the connection structure between the fan motor 7 and the main board 60 . FIG. 5 is an enlarged view showing the vicinity of a stud bolt 40 (described later) in FIG. 3 .

<Structure of fan motor>

First, the structure of the fan motor 7 will be described

The fan motor 7 is an outer rotor type motor, and mainly includes a stator 10 and a cup-shaped rotor 20 that faces the main plate 60 and is arranged on the outer peripheral side of the stator 10 . Furthermore, the fan motor 7 has: a motor base 30 fixed to the top plate 2 a of the case 2 ; and a fixed shaft 31 extending from the motor base 30 toward the main board 60 side. The motor base 30 is a substantially triangular plate-shaped member facing the top plate 2a, and notches 32 for fixing to the top plate 2a with bolts or the like are formed on its outer peripheral portion. The fixed shaft 31 is a cylindrical member centered on the rotation axis O, and is fixed to the central portion of the motor base 30 in a non-rotatable manner. In addition, a vent hole 33 penetrating in the direction of the rotation axis O is formed in the motor base 30 . In addition, the shape of the motor base 30 may not be a substantially triangular plate shape but another shape such as a circular plate shape, and the notch 32 for fixing to the top plate 2a may be a hole.

The stator 10 is a substantially cylindrical member disposed on the outer peripheral side of the fixed shaft 31 and fixed to the motor base 30 . Here, the stator 10 is arranged on the motor base 30 so as not to block the air hole 33 . The stator 10 mainly includes: a stator core 11 made of a magnetic body; and a stator winding 12 wound around the stator core 11.

The rotor 20 mainly has: a substantially disc-shaped rotor flat plate portion 21 facing the hub portion 61 of the main plate 60; and a substantially cylindrical rotor outer cylinder portion 22 extending along the rotation axis O Extends toward the motor base 30 side. The rotor outer cylinder portion 22 has a magnetic pole piece 23 that supplies a field magnetic flux to the stator 10 . The magnetic pole piece 23 faces the outer peripheral surface of the stator 10 across an air gap. Further, the rotor 20 has a substantially cylindrical rotor inner cylinder portion 24 extending from the inner peripheral portion of the rotor flat plate portion 21 toward the motor base 30 side along the rotation axis O. The rotor inner cylinder portion 24 is disposed on the outer peripheral side of the fixed shaft 31 and on the inner peripheral side of the stator 10 , and is rotatably supported by the fixed shaft 31 via bearings 34 and 35 . That is, the rotor 20 is disposed rotatably about the rotation axis O with respect to the stator 10 integrated with the fixed shaft 31 via the motor base 30 . In addition, a vent hole 25 penetrating in the direction of the rotation axis O is formed in the rotor flat plate portion 21 . Here, the vent holes 25 are elongated holes arranged in a plurality of (here, three) rings around the rotation axis O. As shown in FIG. That is, the fan motor 7 is formed with a structure that allows motor cooling air to flow through the space where the stator 10 formed by the rotor 20 and the motor base 30 is arranged through the vent holes 25, 33 (refer to FIG. Arrows showing air flow).

<The connection structure between the fan motor and the motherboard>

Next, a connection structure between the rotor 20 of the fan motor 7 and the main plate 60 of the impeller 8 will be described.

The fan motor 7 is provided with a stud bolt 40 extending from the rotor 20 along the rotation axis O toward the main plate 60 side. The stud bolt 40 is screwed into the threaded hole 26 formed in the radially central portion of the rotor plate portion 21 of the rotor 20 . The threaded holes 26 and the stud bolts 40 are arranged in a plurality of (here, three) annularly around the rotation axis O, and are arranged between the ventilation holes 25 in the circumferential direction here. The stud bolt 40 mainly has: a motor side threaded portion 41, which is screwed into the threaded hole 26; a main plate side threaded portion 42, which is screwed with a washer nut 45 (described later); and a shoulder portion 43, which is formed on the motor side. Between the side threaded portion 41 and the rotation axis O direction of the main plate side threaded portion 42 . The shoulder portion 43 has a cylindrical shape with a larger diameter than the motor-side threaded portion 41 and the main plate-side threaded portion 42. Therefore, the motor-side threaded portion 41 of the stud 40 is screwed and inserted into the threaded hole 26 until the end surface of the shoulder 43 on the motor-side threaded portion 41 side comes into contact with the surrounding portion of the threaded hole 26 . In addition, the dimension of the rotation axis O direction of the shoulder portion 43 is set to be the thickness ( Regarding the elastic members 50 , 55 , and 80 , the amount of compression is taken into consideration) are the same.

A first elastic member 50 and a third elastic member 55 made of rubber are provided in the fan motor 7 provided with the stud bolt 40 . The first elastic member 50 is a substantially disc-shaped member having the same diameter as the rotor flat plate portion 21 of the rotor 20 , and is arranged to overlap the rotor flat plate portion 21 in the rotation axis O direction. A plurality of (here, three) through-holes 51 through which the shoulders 43 of the stud bolts 40 can be inserted are formed at positions of the first elastic member 50 facing the threaded holes 26 of the rotor 20 . Therefore, the first elastic member 50 overlaps the rotor flat plate portion 21 in the rotation axis O direction in a state where the shoulder portion 43 of the stud bolt 40 is inserted into the through hole 51 . In addition, a vent hole 52 is formed at a position of the first elastic member 50 facing the vent hole 25 formed in the rotor flat plate portion 21 . The third elastic member 55 is a substantially cylindrical member through which the shoulder portion 43 of the stud bolt 40 is inserted, and is a member integrated with the first elastic member 50 here. In addition, the third elastic component 55 may also be a separate component from the first elastic component, but it is more preferred to be a component integrated with the first elastic component 50 from the perspective of assembly.

The main plate 60 of the impeller 8 is provided in the fan motor 7 provided with the stud bolt 40 and the first elastic member 50 and the third elastic member 55 . The hub portion 61 of the main plate 60 has a substantially disc-shaped portion having a diameter larger than the rotor plate portion 21 of the rotor 20 and the first elastic member 50 , and is arranged to overlap the first elastic member 50 in the direction of the rotation axis O. A plurality of (here, three) through-holes 62 are formed at positions facing the threaded holes 26 of the rotor 20 on the hub portion 61, and these through-holes allow the shoulder portion 43 in which the stud bolt 40 is inserted therethrough. The third elastic member 55 is inserted through. Therefore, in a state where the third elastic member 55 is inserted into the through hole 62, the hub portion 61 overlaps the first elastic member 50 in the direction of the rotation axis O. That is, the first elastic member 50 is disposed between the main plate 60 and the rotor 20 . In addition, a third elastic member 55 is disposed between the stud bolt 40 and the main plate 60 . In addition, the centering of the fan motor 7 and the main board 60 can be achieved through three stud bolts 40 . In addition, a vent hole 63 is formed at a position facing the vent holes 25 and 52 formed in the rotor flat plate portion 21 and the first elastic member 50 on the hub portion 61 .

A second elastic member 80 made of rubber is provided in the fan motor 7 provided with the stud bolt 40 , the first elastic member 50 and the third elastic member 55 , and the main plate 60 . The second elastic member 80 is a substantially disk-shaped member having a smaller diameter than the rotor flat portion 21 of the rotor 20 and the first elastic member 50, and is arranged to overlap the hub portion 61 of the main plate 60 in the direction of the rotation axis O. A plurality of (here, three) through-holes 81 are formed at a position of the second elastic member 80 facing the threaded hole 26 of the rotor 20 , and the through-holes allow the shoulder 43 through which the stud bolt 40 is inserted. The third elastic member 55 in the state is inserted through. Therefore, in a state where the third elastic member 55 is inserted into the through hole 81 , the second elastic member 80 overlaps the hub portion 61 in the rotation axis O direction.

In the fan motor 7 provided with the stud bolts 40, the first to third elastic members 50, 55, 80 and the main board 60, a rigid member 90 having a higher rigidity than the main board 60 is provided. For example, the rigid member 90 is made of a metal member. The rigid member 90 is a substantially disc-shaped member having a larger diameter than the second elastic member 80 , and is arranged so as to overlap the second elastic member 80 in the rotation axis O direction. A plurality of (here, three) through holes 91 through which the shoulders 43 of the stud bolts 40 can be inserted are formed at positions of the rigid member 90 facing the threaded holes 26 of the rotor 20 . Therefore, the rigid member 90 overlaps the second elastic member 80 in the rotation axis O direction in a state where the shoulder portion 43 of the stud bolt 40 is inserted through the through hole 91 . That is, the rigid member 90 is disposed so as to sandwich the main board 60 between the rigid member and the rotor 20 , and the second elastic member 80 is disposed between the main board 60 and the rigid member 90 . In addition, vent holes 92 are formed at positions facing the vent holes 25 , 52 , and 63 formed in the rotor flat plate portion 21 , the first elastic member 50 , and the main plate 60 of the rigid member 90 . Therefore, in the centrifugal fan 4, the following structure is formed not only in the fan motor 7 but also in the scope of the connection structure between the rotor 20 and the main board 60 including the main board 60, the elastic members 50, 55, 80, and the rigid member 90. (that is, vent holes 25, 52, 63, 92), this structure is used to allow motor cooling air to flow through the space in which the stator 10 formed by the rotor 20 and the motor base 30 is arranged (refer to the air shown in FIG. flow arrows).

In the state where the stud bolt 40 , the first to third elastic members 50 , 55 , 80 , the main plate 60 and the rigid member 90 are arranged so as to overlap the rotor 20 in the direction of the rotation axis O, the rigid member 90 from the stud bolt 40 The nuts with washers 45 are screwed together at the end of the side, and the rotor 20 , the main plate 60 and the rigid member 90 are fixed to each other. Here, the nut with washer 45 is screwed and inserted into the main plate side threaded portion 42 of the stud bolt 40 until the washer portion 46 of the washer nut 45 is on the side of the main plate side threaded portion 42 of the shoulder portion 43 of the stud bolt 40 . until the end faces of the In this state, the end surface of the nut with washer 45 on the opposite side to the washer portion 46 and the end surface of the main plate side threaded portion 42 on the opposite side to the shoulder portion 43 are set to be on the same plane. Thereby, the tightening amount of the nut with washer 45 can be managed.

(3) Characteristics of the centrifugal fan

The coupling structure between the main plate 60 of the impeller 8 in the centrifugal fan 4 and the fan motor has the following characteristics.

(A)

Here, as described above, the rigid member 90 is arranged to sandwich the main board 60 between the rigid member and the rotor 20, and the first elastic member 50 is arranged between the main board 60 and the rotor 20, and the main board 60 and the rigid member The second elastic member 80 is arranged between the 90, and in this state, the rotor 20, the main plate 60 and the rigid member 90 are fixed.

Therefore, here, the degree of deformation such that the main plate 60 is inclined relative to the rotor 20 during transportation can be suppressed by the rigid member 90 disposed so as to sandwich the main plate 60 with the rotor 20 . In particular, here, since the rotor 20, the main board 60, and the rigid member 90 are fixed by the bolts 40, when the main board 60 is deformed such that the main board 60 is inclined relative to the rotor 20 during transportation, the bolts 40 are inserted through the main board 60. In the part and its peripheral part, the main board 60 may be cracked. However, here, since the degree of deformation can be suppressed by the rigid member 90, occurrence of cracks in the main plate 60 can be suppressed. In particular, since the diameter of the rigid member 90 is made larger than the diameter of the second elastic member 80 as described above, the degree of deformation such that the main plate 60 is inclined can be sufficiently suppressed.

In addition, here, noise during operation can be reduced by the second elastic member 80 disposed between the main plate 60 and the rigid member 90 . Here, as described above, the diameter of the second elastic member 80 is made smaller than the diameter of the first elastic member 50 to suppress the contact area of the second elastic member 80 with the hub portion 61 of the main plate 60 to be small. In addition, by making the diameter of the second elastic member 80 smaller than that of the rigid member 90 , the contact area between the second elastic member 80 and the rigid member 90 is kept small. Accordingly, the area where the vibration propagates from the rotor 20 side to the rigid member 90 side becomes smaller, and the effect of suppressing the generation of noise during operation can be further enhanced. Here, if the diameter of the second elastic member 80 is larger than the diameter of the first elastic member 50, and the diameter of the second elastic member 80 is larger than the diameter of the rigid member 90, then the second elastic member 80 is compatible with the hub portion 61 and the rigid member 90. The contact area of the member 90 increases, and the area through which the vibration propagates also increases, so there is a possibility that noise during operation may increase.

In this way, here, in addition to the first elastic member 50 arranged between the main board 60 and the rotor 20, the rigid member 90 is arranged so as to sandwich the main board 60 between the main board 60 and the rotor 20, and the main board 60 and the rigid member The second elastic member 80 is arranged between the 90, so that the main plate 60 of the impeller 80 can be prevented from being damaged during transportation, and the noise during operation can be sufficiently reduced.

<B>

If the main board 60 is in direct contact with the bolt 40 at the part where the bolt 40 is inserted through the main board 60, the vibration will propagate between the main board 60 and the rotor 20 through the bolt 40, and it is possible to use the first elastic member 50 and the second elastic member. 80 to reduce the effect of noise during operation to bring adverse effects.

Therefore, here, as described above, the third elastic member 55 is arranged between the bolt 40 and the main plate 60 to avoid direct contact between the main plate 60 and the bolt 40 .

Accordingly, here, the effect of reducing noise during operation by the first elastic member 50 and the second elastic member 80 can be sufficiently obtained.

<C>

Here, as described above, by making the third elastic member 55 an integral member with the first elastic member 50, the number of elastic members can be reduced, and therefore, the assembly when connecting the main plate 60 and the outer rotor type motor 7 can be improved. sex. In addition, from the viewpoint of reducing the number of elastic members, the third elastic member 55 may be formed integrally with the second elastic member 80 . However, it is more preferable to make the third elastic member 55 integral with the first elastic member 50 from the viewpoint of assemblability when the members 50, 55, 60, 80 are sequentially stacked on the outer rotor type motor 7. part.

<D>

Here, as described above, since the three or more bolts 40 are arranged annularly around the rotation axis O, the outer rotor type motor 7 and the main plate 60 can be reliably centered.

<E>

Here, as described above, the bolt 40 extends from the rotor 20 toward the rigid member 90 , and the rotor 20 , the main plate 60 , and the rigid member 90 are fixed in a state where the nut 45 is screwed from the end of the bolt 40 on the rigid member 90 side. .

Therefore, here, when the rotor 20 , the main plate 60 , and the rigid member 90 are fixed by the bolt 40 , since the nut 45 is screwed from the end of the bolt 40 on the rigid member 90 side, the bolt 40 can be inserted through the elastic member 50 . , 55 , 80 , the main board 60 and the rigid part 90 simultaneously make the elastic parts 50 , 55 , 80 , the main board 60 and the rigid part 90 overlap with respect to the rotor 20 in sequence. Here, if the bolt 40 is inserted from the side of the rigid member 90 toward the side of the rotor 20 instead of extending from the rotor 20 toward the side of the rigid member 90 , it is necessary to make the plurality of members 90 , 80 , 60 , 55 , 50 in advance with the plurality of members 90 . , 80, 60, 55, 50 holes are aligned in the same way, so poor assembly. In addition, when fastening the rotor 20 , the main plate 60 , and the rigid member 90 , the tightening amount of the nut 45 can also be managed with reference to the end position of the bolt 40 .

Therefore, here, the assemblability when connecting the main plate 60 and the outer rotor type motor 7 can be improved, and the nut 45 including the compression amount of the elastic members 50, 55, 80 that affect the noise reduction effect during operation can be managed. The fastening amount of the rotor 20 , the main plate 60 and the rigid member 90 can be properly fixed by the bolts 40 .

In addition, here, as described above, the dimension in the direction of the rotation axis O of the shoulder portion 43 of the bolt 40 is set to be equal to the thickness in the direction of the rotation axis O of the total of the main plate 60 , the rigid member 90 and the elastic members 50 , 55 , and 80 . (Regarding the elastic members 50, 55, 80, considering the amount of compression) are the same, and the nut 45 is screwed and inserted into the main plate side threaded portion 42 of the bolt 40 until the washer portion 46 of the nut 45 becomes in contact with the shoulder portion 43 of the bolt 40 until the end surface on the side of the main plate side threaded portion 42 is in contact with each other. That is, the tightening amount of the nut 45 can also be managed by the shoulder portion 43 of the bolt 40 .

Industrial availability

The utility model can be widely applied to a centrifugal fan whose impeller is driven to rotate by an outer rotor type motor.

Claims (6)

1. A centrifugal fan (4), which has: an impeller (8) having: a plurality of blades (70) arranged annularly about the axis of rotation; and a main plate (60) joining said blades; and an outer rotor type motor (7), which has a stator (10) and a cup-shaped rotor (20), the rotor is opposed to the main plate and is arranged on the outer peripheral side of the stator, The centrifugal fan is characterized in that, A rigid member (90) is arranged to sandwich the main board with the rotor, and a first elastic member (50) is arranged between the main board and the rotor, and between the main board and the A second elastic component (80) is arranged between the rigid components, and in this state, the rotor, the main board and the rigid components are fixed. 2. The centrifugal fan according to claim 1, characterized in that, The rotor, the main board and the rigid component are fixed by bolts (40). 3. The centrifugal fan according to claim 2, characterized in that, A third elastic member (55) is arranged between the bolt and the main board. 4. The centrifugal fan according to claim 3, characterized in that, The third elastic member is a member integral with the first elastic member or the second elastic member. 5. The centrifugal fan according to any one of claims 2 to 4, characterized in that, There are more than three bolts, which are arranged in a ring shape around the rotation axis. 6. The centrifugal fan according to any one of claims 2 to 4, characterized in that, the bolt extends from the rotor toward the rigid member side, The rotor, the main plate, and the rigid member are fixed in a state where a nut (45) is screwed from an end of the bolt on the rigid member side.