JPH11148493A - Air blower - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a means how to assemble a fan onto an outer rotor type electric motor. SOLUTION: In this air blower, a ventilating hole part 731 is formed in a magnet rotor 73a, and concurrently, a projected part 721 to be, inserted in the hole part 731 is formed in the boss part 71a of a fan 72 so as to allow the fan 72 to be stopped in whirl. Furthermore, a projected rib 722 is formed at the boss part 71a, and the fan 72 is fixed with the magnet rotor 73a by means of interference fit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blower using an outer rotor type electric motor, and is effective when applied to a blower of a vehicle air conditioner.

[0002]

2. Description of the Related Art Since a blower of a vehicle air conditioner is mounted on a vehicle, there is a strong demand for downsizing, particularly, unlike a blower installed in a structure such as a building. Therefore, the present inventors have studied and developed a blower that uses an outer rotor type electric motor having a rotor portion outside the stator portion and reduces the height (dimension in the rotation axis direction) of the blower.

[0003] When a fan is assembled to an electric motor, it is common practice to fix the fan to a rotating shaft of the electric motor.

[0004]

However, in the above-mentioned means, for example, when the diameter of the fan is enlarged in order to increase the amount of air blow, the driving torque of the fan becomes large. There is a high possibility that various problems such as slipping with respect to the rotation axis will occur. In view of the above, an object of the present invention is to provide an effective means when assembling a fan to an outer rotor type electric motor.

[0005]

The present invention uses the following technical means to achieve the above object. Claim 1
According to the invention described in 3, the part of the rotor part (73a) facing the boss part (71a) and displaced radially outward from the rotation shaft (73d) of the electric motor (73) includes: A hole (731) is formed, while the boss (71a) faces the rotor (73a) on the side facing the rotor (73a).
a) a projection (721) inserted into the hole (731) and formed toward the side a).

By inserting the projection (721) into the hole (731) formed at a position shifted radially outward, the fan (72) is prevented from rotating with respect to the rotor (73a). Therefore, the force acting on the hole (731) and the protrusion (721) is applied to the fan (72) by forming a chamfered portion such as a two-sided width on the rotating shaft of the electric motor (73). The size can be reduced as compared with a case where the rotation is fixed to the shaft.

Therefore, since a large driving torque can be applied to the fan (72), the blower according to the present invention can drive the fan (72) having a large fan diameter. As described later, the outer rotor type electric motor (73) generates a large amount of heat in the electric motor (73), and a ventilation opening through which cooling air for cooling the electric motor (73) flows is essential.

Therefore, according to the second aspect of the present invention, the hole (731) is formed so as to penetrate the inside and outside of the rotor (73a), and the number of the holes (721) is increased by the number of the protrusions (731).
It is characterized in that the number is larger than the number. Thereby, since the cooling air can be circulated in the electric motor (73), the durability (reliability) of the electric motor (73) can be improved.

According to the third aspect of the present invention, the hole (731) is formed so as to penetrate the inside and outside of the rotor (721), and the cross-sectional area of the hole (731) is increased by the protrusion (721).
Is characterized in that it is larger than the cross-sectional area. Thereby, since the cooling air can be circulated in the electric motor (73), the durability (reliability) of the electric motor (73) can be improved.

Further, since the hole (731) and the ventilation port can be used in common, there is no need to newly provide a hole (731) or a ventilation port. Therefore, the number of manufacturing steps of the blower can be reduced, so that the manufacturing cost of the blower can be reduced. According to the fourth and fifth aspects of the present invention, the contact portion (722) of the boss portion (71a) that contacts the outer circumferential wall surface (73c) at a predetermined surface pressure on the side facing the rotor portion (73b). Is formed.

This makes it possible to press-fit the rotor portion (73a) into the fan (72) with an interference fit, thereby preventing the fan (72) from falling off (falling out) from the electric motor (73). can do. Further, since the rotor portion (73a) and the fan (72) are press-fitted and fixed, the rattling of the fan (72) during rotation of the electric motor (73) can be prevented. Vibration and noise can be prevented.

According to the invention described in claim 5, in the contact portion (72)
2) is formed by a projection projecting from the boss portion (71a) toward the outer circumferential wall surface (73c), and has a tip contacting the outer circumferential wall surface (73c). And As a result, the surface pressure between the contact portion (722) and the outer peripheral wall surface (73c) can be increased as compared with the case where the entire boss portion (71a) is brought into contact with the outer peripheral wall surface (73c). It is possible to reliably prevent the fan (72) from falling off (falling out) from the electric motor (73).

The reference numerals in parentheses of the above means indicate the correspondence with the concrete means described in the embodiments described later.

[0014]

FIG. 1 is a schematic diagram showing a case where a centrifugal blower (hereinafter abbreviated as a blower) according to the present embodiment is applied to an air conditioner 1 for a vehicle equipped with a water-cooled engine. In the air upstream side portion of the air conditioning casing 2 forming an air flow path,
An inside air inlet 3 for sucking vehicle interior air and an outside air inlet 4 for sucking outside air are formed, and an inlet switching door 5 for selectively opening and closing these inlets 3, 4 is provided. Have been. The inlet switching door 5 is opened and closed by driving means such as a servomotor or by manual operation.

At the downstream side of the inlet switching door 5,
A filter F for removing dust from the air and a blower 7 according to the present embodiment are provided, and the air sucked from the suction ports 3 and 4 by the blower 7 is used to blow air to each of the outlets 14, 15, which will be described later. It is blown toward 17. Blower 7
An evaporator 9 serving as an air cooling means is disposed downstream of the air, and all the air blown by the blower 7 passes through the evaporator 9. A heater core 10 serving as air heating means is provided downstream of the evaporator 9 in the air. The heater core 10 heats the air using the cooling water of the engine 11 as a heat source. In addition, the drawing of the blower shown in FIG. 1 is a schematic diagram, and details will be described later.

In the air-conditioning casing 2, a bypass passage 12 for bypassing the heater core 10 is formed.
An air mix door 13 that adjusts the ratio of the amount of air flowing through the air passage to the amount of air flowing through the bypass passage 12 is provided. The adjustment of the air volume ratio is adjusted by adjusting the opening of the air mix door 13.

A face outlet 14 for blowing air-conditioned air to the upper body of the passenger in the passenger compartment, and a foot outlet 15 for blowing air to the feet of the passenger in the passenger compartment are provided at the most downstream side of the air-conditioning casing 2. Defroster outlet 1 for blowing air toward the inner surface of windshield 16
7 are formed. Each of the outlets 14, 1
Blow-out mode switching doors 18, 19, and 20 are provided at air upstream portions of the air conditioners 5 and 17, respectively. Note that these blowout mode switching doors 18, 19, 20 are opened and closed by driving means such as a servomotor or by manual operation.

In the actual vehicle air conditioner, since the foot outlet 15 and the defroster outlet 17 are smaller than the face outlet 14, the foot mode and the differential mode have a lower air flow resistance than the face mode. Pressure loss) has increased. Next, the blower 7 will be described in detail.

As shown in FIG. 2, the blower 7 is a centrifugal blower that blows out air taken in from the direction of the rotating shaft toward the outside in the radial direction. Reference numeral 72 denotes a large number of blades 71 around the rotating shaft. This is a well-known centrifugal multi-blade fan 72 (hereinafter abbreviated as a fan) having a boss portion 71a for holding a plurality of blades 71. In addition, as shown in FIG. 3, the fan 72 according to the present embodiment alternately arranges the blades 71 having different blade lengths L and sets the outlet angle β of the blade 71 to 90 ± 25 degrees (in the present embodiment, Radial fan within about 90 degrees.

Incidentally, as shown in FIG. 6, the blade length L refers to the length of the blade 71 measured in parallel to the radial direction of the fan 72, and the exit angle β refers to the blade 71 and the fan 71. 72 is the angle of intersection with the outer diameter edge of the fan 72, measured from the forward side in the rotational direction of the fan 72. As shown in FIG. 2, the fan 72 is driven to rotate by an electric motor (hereinafter, abbreviated as “motor”) 73, and the amount of air blown is controlled by controlling the number of rotations of the motor 73. Have been done. The motor 73 is
A substantially cylindrical magnet rotor portion (hereinafter abbreviated as a rotor) 73a having a permanent magnet adhered to the inner wall is disposed outside a stator coil portion 73b including an excitation coil and the like.
This is a so-called outer rotor type electric motor.

Here, the assembly structure of the fan 72 and the motor 73 will be described. FIG. 4 is an enlarged view of a portion A in FIG. 2, and a portion of the rotor 73 a facing the boss portion 71 a and offset from the rotation shaft 73 d of the motor 73 to the radially outward side is a portion of the rotor 73 a. Hole 7 penetrating inside and outside
31 are concentric with the rotating shaft 73d (see FIG. 3)
On the other hand, three portions of the boss portion 71a facing the rotor 73a and corresponding to the holes 731 protrude toward the rotor 73a and have the holes 73a.
1 are integrally formed with the projection 721.

When the protrusion 721 is inserted into the hole 731, the sectional area of the hole 731 is adjusted so that a gap δ is generated between the hole 731 and the protrusion 721.
By making the cross-sectional area larger than 1, the cooling air that cools the motor 73 also functions as a ventilation port. On the side of the boss portion 71a facing the rotor 73a, a triangular protruding rib (which protrudes toward the circumferential outer wall surface 73c of the rotor 73a and comes into contact with the circumferential outer wall surface 73c at a predetermined surface pressure). As shown in FIG. 3, three contact portions 722 are formed around the rotation shaft 73a of the motor 73 at equal intervals. Incidentally, in the present embodiment, the protruding rib 722, the protrusion 721,
The blade 71 and the boss 71a are integrally formed of resin.

The fan 72 stops the fan 72 from rotating with respect to the rotor 73a (motor 73) by inserting the protrusion 721 into the hole 731. The three protruding ribs 722 are connected to the circumferential outer wall surface. By bringing the rotor 73a (motor 73) into contact with the fan 72 (projecting rib 722) with an interference fit by contacting the rotor 73c (motor 73) with a predetermined surface pressure, the fan 72 drops off (exits) from the motor 73. Is preventing that.

In FIG. 2, reference numeral 74 denotes a housing for accommodating the fan 72 and an air flow passage 74a through which air blown from the fan 72 flows. The air passage 74a is made of a material such as polypropylene spirally formed around the rotation axis of the fan 72. In a scroll casing made of resin (hereinafter abbreviated as casing), an outlet 75 communicating with the air-conditioning casing 2 is formed downstream of the winding end portion 74b of the casing 74 in the air (see FIG. 3).

The casing 7 is disposed on the opposite side of the motor 73 in the direction of the rotation axis of the casing 74.
A suction port 76 for leading air into the inside of the air inlet 4 is opened, and a bell mouth 77 formed in a bell mouth shape is formed at an opening outer edge 65a of the suction port 76. An air flow whose radial cross section is turned radially outward from the suction port 76 at the end 71 a of the blade 71 on the suction port 76 side at the radially outer end of the fan 72. An annular shroud 78 having a shape along the shape is formed. On the other hand, in the vicinity of the bell mouth 77 of the casing 74, the shroud 78 faces the shroud 78 with a predetermined gap 78b, and is radially outward from the bell mouth 77. Shroud 7
The opposite bent wall 79 which bends smoothly along the shape of 8
Are formed.

Next, the features of this embodiment will be described. According to the present embodiment, the protrusion 721 formed on the fan 72 (the boss 71a) is inserted into the hole 731 formed on the rotor 73a at a position shifted radially outward from the rotation shaft 73d. As a result, the fan 72 is prevented from rotating with respect to the rotor 73a (motor 73).
The fan 72 is fixed to the rotating shaft 73d to prevent the fan 72 from rotating, so that the fan 72 can be reduced in size.

Therefore, since a large driving torque can be applied to the fan 72, the blower according to the present embodiment can drive the fan 72 having a large fan diameter. Further, the blower 7 according to the present embodiment
Can drive the fan 72 having a large fan diameter, and is particularly effective when applied to a vehicle air conditioner having a filter F as in the present embodiment and having a large ventilation resistance.

By the way, the outer rotor type motor 73
Has a control circuit (not shown) for controlling the rotation of the motor 73 in the rotor 73a, so that the amount of heat generated in the motor 73 (rotor 73a) is large, and cooling air for cooling the motor 73 flows. Ventilation openings are mandatory. On the contrary,
In the present embodiment, since the hole 731 is also used as a ventilation port, it is not necessary to newly provide a hole 731 (or a ventilation port). Therefore, the number of manufacturing steps of the blower 7 can be reduced, and the manufacturing cost of the blower 7 can be reduced.

Further, in this embodiment, since the number of the holes 731 is larger than the number of the projections 721, the cooling air can be circulated in the motor 73 more reliably. ) Can be improved. Further, as shown in FIG. 4, since the tip of the protruding rib 722 is brought into contact with the outer peripheral wall surface 73c of the rotor 73a to press the rotor 73a into the fan 72, the entire boss portion 71a is inserted into the outer peripheral wall surface 73c. As compared with the case of contacting,
It is possible to increase the surface pressure between the outer peripheral wall surface 73c and the outer peripheral wall 73c. Therefore, it is possible to reliably prevent the fan 72 from dropping (falling out) from the motor 73.

Since the rotor 73a and the fan 72 are press-fitted and fixed, the fan 72
Can be prevented from rattling, so that vibration and noise of the fan 72 due to rattling can be prevented. By the way, in the above-described embodiment, the number of the holes 731 is larger than the number of the protrusions 721. However, as described above, if the cross-sectional area of the holes 731 is larger than the cross-sectional area of the protrusions 721, the present invention May have the same number of both 721 and 731.

In the above-described embodiment, the cross-sectional area of the hole 731 is larger than the cross-sectional area of the protrusion 721. However, if the number of the holes 731 is larger than the number of the protrusions 721, the present invention will be described. Alternatively, the cross-sectional areas of the two 721 and 731 may be the same (the gap δ is eliminated). Further, in the above-described embodiment, the hole 731 also serves as the ventilation port, but both may be formed independently. In this case, the hole 7
31 does not need to penetrate inside and outside the rotor 73a, and may be a concave hole which is depressed toward the inside of the rotor 73a.

In the above embodiment, the projecting rib 72
2 is formed in a triangular shape, but instead of the triangular protruding rib 722, a ring-shaped protruding rib protruding toward the circumferential outer wall surface 73c may be used. In addition,
In this case, the number of the protruding ribs may be plural as well as one. The rotor 73a (motor 73) and the fan 72
In order to secure the tight fit with the (projecting rib 722), the projecting dimension of the projecting rib 722 is increased from the motor 73 side to the suction port 76 side, and the projecting rib 722 is tapered. Is also good.

The protruding rib 722 of the rotor 73a
The rotor 73a is located at
May be formed (see FIG. 5). In this case, since the groove and the protruding rib 722 can perform the function of preventing the fan 72 from rotating and preventing the fan 72 from falling off, the protrusion 721 may be omitted.

In the above-described embodiment, the fan 72 and the motor 73 are tightly fitted by using the protruding rib 722 to prevent the fan 72 from falling off.
An engaging means such as a claws may be used for the motor 2 and the motor 73.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a vehicle air conditioner.

FIG. 2 is a sectional view of the blower cut in an axial direction.

FIG. 3 is a cross-sectional view of the blower cut in a direction orthogonal to the axial direction.

FIG. 4 is an enlarged view of a portion A in FIG. 2;

FIG. 5 is a front view of a blower (excluding a casing) according to a modified example of the present invention.

FIG. 6 is an explanatory diagram of an exit angle β.

[Explanation of symbols]

71: Blade, 71a: Boss part, 72: Centrifugal multi-blade fan, 721: Projection part, 722: Projecting rib (contact part) 73
... Electric motor 73a ... magnet rotor, 73b ... stator coil,
731 ... hole.

Claims (5)

[Claims] A fan (7) for blowing air having a plurality of blades (71) arranged around a rotation axis and a boss (71a) for holding said plurality of blades (71).
2) and an outer rotor type electric motor (73) having a rotor portion (73a) outside the stator portion (73b) while rotating the fan (72), and the rotor portion (73a). Of the side facing the boss portion (71a), a portion shifted radially outward from the rotation shaft (73d) of the electric motor (73) is a hole (73).
1) is formed, and on the side of the boss (71a) facing the rotor (73a), the boss protrudes toward the rotor (73a) and is inserted into the hole (731). A blower (721) formed thereon. 2. The hole (731) is formed so as to penetrate the inside and outside of the rotor (73a), and the number of the holes (721) is larger than the number of the protrusions (731). The blower according to claim 1, wherein: The hole (731) is provided in the rotor (7).
21) The hole (731) and the protrusion (721) are formed so as to penetrate inside and outside, and the protrusion (721) is inserted into the hole (731).
2. The blower according to claim 1, wherein a cross-sectional area of the hole (731) is larger than a cross-sectional area of the protrusion (721) so that a gap is generated between the blower and the protrusion. 4. A fan (7) for blowing air having a plurality of blades (71) arranged around a rotation axis and a boss (71a) for holding said plurality of blades (71).
2) and an outer-rotor-type electric motor (73) that rotates the fan (72) and that has a rotor portion (73a) outside the stator portion (73b). The rotor portion (73b) Has a circumferential outer wall surface (7
3c) is formed on the side of the boss portion (71a) facing the rotor portion (73b) at a predetermined surface pressure.
A blower characterized by having a contact portion (722) for contacting the air blower. 5. The contact portion (722) is formed by a projection projecting from the boss portion (71a) toward the circumferential outer wall surface (73c), and has a distal end at which the contact portion (722) extends outside the circumferential surface. The blower according to claim 4, wherein the blower is in contact with a wall surface (73c).