JPH0533660U - Air conditioning fan drive motor - Google Patents

Abstract

(57) [Abstract] [Purpose] In an air-conditioning fan drive electric motor having an outer rotor type rotor that rotates around a fixed axis, the rotor support structure is improved to reduce vibration and fretting phenomenon. [Structure] First and second bearings A and B are arranged on a boss 60 provided on the rotor 6, and thereby the rotor 6 is supported on the shaft body 4. Only the outer ring 92 of the first bearing A is press-fitted, and the others are made to have a loose fitting support structure, and a pressure washer is applied to both bearings A and B by utilizing the wave washer 99 and the spacer 97, whereby the bearing A,
It prevents the rattling of B and the following rotation of the inner and outer rings.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an electric motor for driving an air conditioning fan such as a cross flow fan used in an indoor unit of an air conditioner.

[0002]

[Prior Art]

 In this type of conventional fan device, a DC brushless motor, which is a finished product, is used (for example, Japanese Utility Model Laid-Open No. 61-178095), and the rotary shaft of the motor is connected via Johnit made of anti-vibration rubber. The rotation of the rotating shaft is transmitted to the fan rotor by directly connecting it to the fan rotor.

[0003]

[Problems to be solved by the device]

 However, in a conventional device using a DC brushless motor, it is difficult to achieve noise reduction because the stator vibrates in the torque direction when the polarity is switched, which causes cogging. Therefore, it is conceivable to use an AC motor, but using an AC motor is inefficient and it is difficult to meet the demand for energy saving. Therefore, attempts have been made to reduce the vibration by using an outer rotor type DC brushless motor and devising its bearing structure.

This invention is based on the use of an outer rotor type DC brushless motor, and the occurrence of the fretting phenomenon of the bearing, which is a problem when using such a DC brushless motor, is ensured with an extremely simple structure. It is an object of the present invention to provide an electric motor for driving an air conditioning fan which can be suppressed to a high level and has excellent reliability.

[0005]

[Means for Solving the Problems]

 Therefore, the air-conditioning fan driving electric motor of the present invention is arranged around the stator 5, the shaft body 4 fixed to the end bracket 3 and protruding from the end bracket 3, the stator 5 attached to the shaft body 4, and the stator 5. The rotor 6 connected to the fan rotor 1, a cylindrical boss 60 extending from the rotor 6, and a ball 93 held between an inner ring 91 and an outer ring 92. Is press-fitted and fixed to one end side of the boss 60, and the inner ring 91 is press-fitted into the shaft body 4 and the end face of the inner ring 91 of the first bearing A is press-fitted into the shaft body 4. The ball 96 is held between the inner ring 94 and the outer ring 95, and the outer ring 95 is loosely fitted on the tip side of the boss 60. A second shaft bearing B in which the inner ring 94 is loosely fitted to the shaft body 4, and a first shaft. A spacer 97 interposed between the outer rings 92 and 95 in a state of contacting the end face of the outer ring 92 of A and the end face of the outer ring 95 of the second bearing B and outside the second bearing B. A second fixed ring 98 fixed to the tip side of the shaft body 4 and a biasing means 99 interposed in a compressed state between the second fixed ring 98 and the inner ring 94 of the second bearing B. is there.

[0006]

[Action]

 According to the air-conditioning fan driving motor of the present invention, the inner ring 94 of the second bearing B moves toward the first bearing A side by the reaction force of the biasing means in the compressed state, for example, the wave washer 99, and as a result, the ball 96 is moved. The outer ring 95 moves through in the same direction. When the outer ring 95 of the second bearing B moves toward the first bearing A side in this manner, the outer ring 95 pushes the spacer 97 in the same direction. On the other hand, the outer ring 92 of the first bearing A is press-fitted and fixed to one end side of the boss 60 extended from the rotor 5, and the inner ring 91 of the first bearing A is fixed by the first fixed ring 57 to the shaft body 4. Since the spacer 97 is moved to the position described above, the outer ring 92 of the first bearing A moves integrally with the boss 60 and the rotor 6 in the same direction by the movement of the spacer 97 as described above. Therefore, the balls 93 and 96 of the first bearing A and the second bearing B have no axial play, which prevents the balls 93 and 96 from jumping during rotation.

The inner ring 94 of the second bearing B is in contact with the second fixed ring 98 fixed to the shaft body 4 and is in contact with the wave washer 99 whose slip and rotation with respect to the shaft body 4 is suppressed. Hard to slip and rotate with respect to body 4. The outer ring 95 of the second bearing B is in contact with the outer ring 92 of the first bearing A press-fitted into the boss 63 and is in contact with the spacer 97 in which sliding rotation with the boss 60 is suppressed. It is hard to slip and rotate. Since the inner ring 91 of the first bearing A is positioned on the shaft body 4 by the first fixed ring 57, it is difficult for the inner ring 91 to slide and rotate with respect to the shaft body 4. Therefore, all the inner races 91, 94 and the outer races 92, 95 of the first bearing A and the second bearing B are less likely to slip and rotate with respect to the boss 60 or the shaft 4 into which they are press-fitted or loosely fitted.

As described above, the fretting phenomenon is suppressed.

The fretting phenomenon is different from the fretting phenomenon in that the sliding portions of the inner rings 91, 94 and outer rings 92, 95 are worn and rusted, and the rust is mixed in the grease of the bearings A, B. It is a phenomenon that produces sound and accelerates the deterioration of grease.

[0010]

【Example】

 Next, a specific embodiment of the air-conditioning fan driving electric motor of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a configuration of a fan device in an indoor unit of an air conditioner, more specifically, a side plate (hereinafter, referred to as a right side plate) 2 side of a fan rotor 1 of a cross flow fan.

Reference numeral 3 denotes an end bracket, in which a face plate portion 31 and a tubular portion 32 are formed by sheet metal working, and a hole portion 33 is formed at a central position of the face plate portion 31, and a hole is provided at an appropriate position. An opening 34 and the like for inserting the element H are formed.

Reference numeral 4 denotes a shaft body, which has a collar portion 41, a portion 42 protruding from the collar portion 41 is fitted into the hole 33 of the face plate portion 31, and the collar portion 41 is spot-welded to the face plate portion 31 or the like. It is fixed by appropriate means. A fixed seat 43 with a collar made of a metal such as aluminum is press-fitted into the base of the shaft body 4 in a state of contacting the collar 41.

Reference numeral 5 denotes a stator, which is an iron core 51 that is electrically insulated by applying powder coating and is equipped with windings 52. The iron core 51 of the stator 5 is fitted onto the cylindrical vibration damping rubber 53, and another cylindrical vibration damping rubber 54 is provided on one side of the iron core 51. Another anti-vibration rubber 54 is attached to the fixed seat 43 via the key 44, and a plurality of protrusions 55 formed on the anti-vibration rubber 54 are fitted into holes 56 formed in the iron core 51. I'm out. When the stator 5 is attached to the shaft body 4 via such two types of vibration-proof rubbers 53 and 54, when the iron core 51 receives a force against the torque, the pulsation of the torque causes the vibration-proof rubbers 53 and 54. Is absorbed by and becomes hard to be transmitted to the shaft body 4. Further, since the anti-vibration rubber 53 is only in contact with the iron core 51 and the shaft body 4 and does not have elements such as keys engaging with them in the rotating direction, the contact surface with them absorbs the pulsation of torque. Therefore, it can be said that the pulsation of the torque is hard to be transmitted to the shaft body 4 by one layer.

A first fixed ring 57 press-fitted and fixed to the shaft body 4 is in contact with an end surface of the vibration-proof rubber 53, and the vibration-proof rubber 53 is axially positioned by the first fixed ring 57. ..

Reference numeral 6 is a rotor. The rotor 6 has a tubular portion 62 extending from the outer peripheral edge of the mounting plate portion 61, and a boss portion 63 protruding inward is formed at the center of the mounting plate portion 61. Further, a joint member 65 having another boss portion 64 protruding outward is fixed to the mounting plate portion 61 with a rivet 66. The joint member 65 and the fan rotor 1 are connected to each other via a flexible joint 67 using vibration-proof rubber.

The above-mentioned two boss portions 63, 64 form a boss 60 for accommodating a first bearing A and a second bearing B, which will be described later. The boss 60 may be an integral body, that is, it may be a cylindrical one extending to the rotor 6 and having the fan rotor 1 attached thereto.

Small holes 68 are formed in the tubular portion 62 at a plurality of circumferential positions.

While the magnet 69 is provided on the inner surface of the tubular portion 62 of the rotor 6, the yoke 70 is fitted over the outer surface of the tubular portion 62 in an overlapping manner. A small hole 71 is formed in the yoke 70 so as to overlap the small hole 69 of the cylindrical portion 62. The magnet 69 extends inside the small holes 68 and 71, and the extended portion is exposed outside the yoke 70 with substantially the same thickness as the yoke 70.

The magnet 67 is compression-molded, including the extended portion, and is magnetized, and is also assembled to the rotor 6 at the same time when the compression molding is performed. That is, the yoke 70 is fitted to the tubular portion 62 of the rotor 6 and placed in a bond magnet molding die, and the magnet material in which the binder is mixed with the magnetic material is placed in the molding die to perform compression molding and heat. It has been cured. In this way, by forming the magnet 69 and the extended portion thereof, they and the tubular portion 62 are fixed to each other, and the manufacture of the magnet 69 and the fixing of parts such as the yoke 70. Is reliably performed in one process, and the man-hours can be reduced and the cogging caused by the improper mounting of the magnet 69 can be suppressed at the same time. When a rare earth material such as neodymium or boron is used as the magnetic material and powdered epoxy resin is used as the binder, a strong magnet 69 can be obtained, and the thickness of the magnet 69 can be reduced to achieve miniaturization.

A board (drive circuit board) 8 on which a drive circuit and the like are mounted is provided on the rear surface side of the face plate portion 31 of the end bracket 3, and a proper position of the board 8 is attached to the face plate portion 31 by a clip 81. A Hall element H is mounted on the substrate 8. The hall element H faces the inner peripheral portion of the magnet 69.

The boss 60 is supported on the shaft body 4 by a first bearing A and a second bearing B. FIG. 2 shows an enlarged mounting structure of the boss 60 and the shaft body 4. The first bearing A comprises a ball 93 held between an inner ring 91 and an outer ring 92, the outer ring 92 is press-fitted and fixed to one end of the boss 60, that is, the boss 63, and the inner ring 91 is fixed to the shaft body 4. It is loosely fitted in a state that it does not have large rattling. The second bearing B is formed by holding a ball 96 between an inner ring 94 and an outer ring 95, and the outer ring 95 has a clearance fit state with no large rattling at the tip of the boss 60, that is, the tip of the boss 64. And the inner ring 94 is loosely fitted to the shaft body 4 in a clearance fit state with no large rattling. Further, a cylindrical spacer 97 is interposed between the outer rings 92, 95 in a state of abutting against the end face of the outer ring 92 of the first bearing A and the end face of the outer ring 95 of the second bearing B. A second fixed ring 98 is fixed to the outside of the second bearing B at the tip of the shaft body 4, and as a biasing means between the second fixed ring 98 and the inner ring 94 of the second bearing B. The wave washer 99 is interposed in a compressed state.

With the configuration of FIG. 2 described above, the outer ring 92 of the first bearing A is press-fitted and fixed to the boss portion 63, and the inner ring 91 thereof is positioned on the shaft body 4 by the first fixed ring 57. The outer ring 95 of the two-shaft bearing B is slidable in the axial direction with respect to the boss portion 64, and the inner ring 94 thereof is slidable in the axial direction with respect to the shaft body 4. Therefore, the reaction force of the wave washer 99 in the compressed state causes the inner ring 94 of the second bearing B to move toward the first bearing A side by the amount of play between the ball 96 and the grooves 94a and 95b in which the ball 96 is fitted. As a result, the groove 96a of the inner ring 94 pushes the ball 96 in the same direction, and the ball 96 moves the outer ring 95 in the same direction via the groove 95b of the outer ring 95. When the outer ring 95 of the second bearing B moves toward the first bearing A side in this manner, the outer ring 95 pushes the spacer 97 in the same direction. By the movement of the spacer 97 in this way, the outer ring 92 of the first bearing A is integrated with the boss 60 and the rotor 6 (see FIG. 1), and the ball 93 and the groove 91a in which the ball 93 is fitted. , 92a move in the same direction as the play. Therefore, the balls 93 and 96 of the first bearing A and the second bearing B do not have the axial play of the bearings A and B, and the situation in which the balls 93 and 96 jump during rotation is prevented. Helps reduce noise and improve service life.

The inner ring 94 of the second bearing B is in contact with the second fixed ring 98 fixed to the shaft body 4 and is in contact with the wave washer 99 whose slip and rotation with respect to the shaft body 4 is suppressed. Hard to slip and rotate with respect to body 4. This action is promoted by fitting the wave washer 99 into the shaft body 4 without any gap. The outer ring 95 of the second bearing B is in contact with the outer ring 92 of the first bearing A press-fitted into the boss 63 and is in contact with the spacer 97 which is prevented from sliding and rotating with the boss 60. On the other hand, it is hard to slip and rotate. Since the inner ring 91 of the first bearing A is positioned on the shaft body 4 by the first fixed ring 57, it is difficult for the inner ring 91 to slide and rotate with respect to the shaft body 4. Therefore, all the inner rings 91, 94 and the outer rings 92, 95 of the first bearing A and the second bearing B are less likely to slip and rotate, and thus the fretting phenomenon is less likely to occur.

An annular groove 98a is formed on the inner surface of the second fixed ring 98, an annular groove 4a is also formed on the shaft body 4, and the groove 98a is filled with a resin adhesive. When the groove 98a and 4a of the both are aligned and the resin adhesive 100 is intervened in the inner space of the groove 98a and 4a by press-fitting into the shaft 4, the second fixing ring 98 is fixed in the axial direction. Power increases. Therefore, the reaction force of the spring washer 99 described above can be sufficiently exerted on the bearings A, B, and the like, and it can sufficiently withstand a large impact such as an accidental drop during transportation.

[0026]

[Effect of the device]

 Although the air-conditioning fan driving electric motor of the present invention uses the outer rotor type motor, the fretting of the bearing can be suppressed with a very simple structure, and the noise is low. Further, since a DC brushless motor can be used, it is possible to provide a device that is small, efficient, and highly reliable.

[Brief description of drawings]

FIG. 1 is a sectional view of an electric motor for driving an air conditioning fan according to an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view of a bearing mounting portion of the above device.

[Explanation of symbols]

 A first bearing B second bearing 1 fan rotor 3 end bracket 4 shaft body 5 stator 6 rotor 57 first fixed ring 60 boss 91 inner ring of first bearing 92 outer ring of first bearing 93 ball of first bearing 94 fourth 2 Inner ring of bearing 95 Outer ring of second bearing 96 Ball of second bearing 97 Spacer 98 Second fixed ring 99 Wave washer

Claims (1)

[Scope of utility model registration request] 1. A shaft body (4) fixed to an end bracket (3) and protruding from the end bracket (3).
A stator (5) attached to the shaft body (4), and arranged around the stator (5), and a fan rotor (1)
A rotor (6) connected to the rotor, a cylindrical boss (60) extending from the rotor (6), an inner ring (91) and an outer ring (9).
A ball (93) is held between the outer ring (9) and
The first bearing (A) in which 2) is press-fitted and fixed to one end side of the boss (60), and the inner ring (91) is loosely fitted in the shaft body (4).
And a first fixed ring that is press-fitted into the shaft body (4) and contacts the end surface of the inner ring (91) of the first bearing (A) to position the first bearing (A) on the shaft body (4) ( 57) and the inner ring (9
4) and the outer ring (95) hold a ball (96), the outer ring (95) is loosely fitted to the tip side of the boss (60), and the inner ring (94) is attached to the shaft body (4). The second bearing (B) loosely fitted, the end surface of the outer ring (92) of the first bearing (A) and the second
Outside the second bearing (B) and the spacer (97) interposed between the outer rings (92) (95) in contact with the end surface of the outer ring (95) of the bearing (B). The second fixed ring (98) fixed to the tip side of the shaft body (4) and the second fixed ring (98) and the inner ring (94) of the second bearing (B) were interposed in a compressed state. An electric motor for driving an air conditioning fan, comprising an urging means (99).