JPH04114753U - Brushless motor bearing structure - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent abnormal noise between the rotor and the main body,
This aims to prevent shaft shivering and seizure of the bearing that supports the rotating shaft, and also to improve the reliability of the motor. [Structure] Bearings 10a and 10b of a rotating shaft 5 that rotatably supports a rotor 3 are fixed to a main body 2 via vibration isolators 11 and 17 made of an elastic body or a low-hardness material.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This idea was developed for the bearing structure of brushless motors, which are mainly used in vehicle air conditioners. related.

0002

[Conventional technology]

Generally, in this type of motor, the axis of the rotating shaft that rotatably supports the rotor is The receiver is directly fixed to the main body (for example, see Japanese Utility Model Application No. 2-97876).

0003

[Problem that the idea aims to solve]

However, as mentioned above, the bearing of the rotating shaft is directly fixed to the main body. If so, the vibration of the rotor that occurs when switching the armature is transmitted from the rotating shaft to the bearing. There was a problem in that the sound was transmitted to the main body via the main body, causing resonance sound.

0004 In addition, if the concentricity of the upper and lower bearings is not accurate, shaft shivering and bearing seizure may occur. This had the problem of causing

[0005] Therefore, in view of the above problems, this idea was developed to eliminate the above problems and improve reliability. The purpose of the present invention is to provide a bearing structure for a brushless motor.

[0006]

[Means to solve the problem]

In order to achieve the above object, the bearing structure of the brushless motor according to this invention is as follows: A rotor that is rotatably provided with a field magnet, and a rotating magnetic field is applied to the rotor. A brushless device comprising an armature that generates electricity and excitation means that excites the armature. In a motor, the bearing of the rotating shaft that rotatably supports the rotor is made of an elastic material or a It is fixed to the main body via a vibration isolating material made of hard material.

[0007]

[Effect] Therefore, a vibration isolating material made of an elastic material or a low hardness material is interposed between the bearing and the main body. Therefore, the vibration isolating material absorbs the vibration of the rotor and does not transmit it to the main body. The force causes the rotating shaft to self-align through the upper and lower bearings, thereby solving the above problem. can be solved.

[0008]

【Example】

Examples of this invention will be described below with reference to the drawings.

[0009] In FIG. 1, the brushless motor 1 is arranged above the center inside the main body 2. Basically consists of a rotor 3 and a printed circuit board 4 placed below the rotor 3. A scirocco-type fan 6 is installed at the tip of the rotating shaft 5 protruding from the main body 2. is installed.

0010 The main body part 2 has a substantially conical shape and is composed of a housing part 7 and a bottom plate 8. A printed circuit board 4, which will be described later, is screwed to the bottom plate 8 of. or, A bearing holding portion 9 is provided approximately at the center of the housing portion 7, and the bearing holding portion 9 One of the bearings 10a, which rotatably supports the rotating shaft 5 inside, is pressed through the vibration isolating material 11. It's in. This vibration isolating material 11 is made of an elastic material such as rubber or synthetic rubber, or a synthetic resin. Made of low hardness material. Note that there are marks (not shown) on the outer peripheral edge of the main body 2. A flange 12 for fixing the brushless motor 1 to the blower unit is provided. ing.

[0011] The rotor 3 is composed of a rotor yoke 13, a boss portion 14, and an annular field magnet 15. The boss portion 14 is press-fitted onto the rotating shaft 5 and is rotatably supported. In addition, the field magnet 15 is multi-pole magnetized in the circumferential direction, and its leakage magnetic flux It is fixed with adhesive etc. in the rotor yoke 13 to suppress the A magnetic field is applied to the moving coil 18.

0012 The printed circuit board 4 has an insulating layer formed on its upper and lower surfaces to carry an excitation circuit (not shown). The excitation circuit is configured to appropriately excite the drive coil 18 described below. It has become. The bearing holding portion 16 provided approximately at the center of the printed circuit board 4 has a The other bearing 10b that rotatably supports the rotary shaft 5 is press-fitted through the vibration isolating material 17. Similar to the vibration isolating material 11 described above, the vibration isolating material 17 is made of elastic material such as rubber or synthetic rubber. It is made of a low hardness material such as a hard material or synthetic resin. Also, surrounding the bearing 10b A plurality of drive coils 18 serving as armatures are arranged at positions facing the field magnet 15. The drive coil 18 is suitably excited by the excitation circuit and is driven by the field of the rotor 3. A rotating magnetic field is applied to the magnet 15.

[0013] Note that 18 is a cable that supplies power to the printed circuit board 4.

[0014] In the above configuration, each drive coil 18 of the brushless motor 1 is excited. Then, a rotating magnetic field is applied to the field magnet 15 of the rotor 3 to rotate the rotor 3, and the rotating shaft is rotated. It operates as a blower motor that rotates a fan 6 via the motor 5. This brushless motor The controller 1 is arranged, for example, in a blower case (not shown) of a vehicle air conditioner, and Used for inhaling and blowing out air.

[0015] However, as described above, the bearing structure of the brushless motor 1 is The bearings 10a and 10b supporting the main body 2 and the main body It is fixed to a printed circuit board 4 which is one of the constituent members of the section 2. This anti-vibration material Since 11 and 17 are made of an elastic material or a low hardness material, the switch of the armature is The vibration of the rotor 3 caused by the cutting is absorbed and the vibration is transmitted to the main body 2. It acts to prevent Therefore, there is resonance between the rotor 3 and the main body 2. This makes it possible to prevent abnormal noise from occurring.

[0016] Also, if the rotating shaft 5 rotates and its position shifts due to centrifugal force, etc. Even if the vibration isolating materials 11 and 17 have elastic force, the rotating shaft 5 returns to its original position. Because of this, self-alignment of the rotating shaft 5 is achieved, preventing shaft shifting, bearing seizure, etc. It is possible to prevent this, and the position of the rotor 3 can be maintained with high accuracy. For example, even if an external force is applied to the rotor 3 from the outside, the vibration isolating materials 11 and 17 To absorb external force, prevent deformation of the inner surfaces of the bearings 10a and 10b and the rotating shaft. I can do it.

[0017] Furthermore, if the centers of the upper and lower bearings 10a and 10b are shifted by a small amount, Since lateral pressure can be applied to the rotating shaft 5 during rotation, the rotating shaft 5 Shaking within the bearings 10a, 10b can be prevented.

[0018] Next, a second embodiment of this invention will be described with reference to FIG. However, the above Components having the same configuration as those in the first embodiment are given the same reference numerals and their explanations are omitted. Only the different points will be explained below.

[0019] The bearing structure in this embodiment differs from that described above in that the bearings 20a, 20b The shape of the bearings 20a and 20b is made into a spherical shape, and the bearings 20a and 20b are protected through vibration isolators 21 and 22. It is located in a place where it is press-fitted into the holding parts 9 and 16. Note that the vibration isolating materials 21 and 22 are Similar to the first embodiment, an elastic material such as rubber or synthetic rubber or a synthetic resin may be used. Made of low hardness material.

[0020] According to this bearing structure, the vibration isolators 21 and 22 support the bearings 20a and 20b in all directions. In addition to the effects of the first embodiment, due to the spherical shape, This has the advantage that the amount of alignment of the rotating shaft 5 can be increased.

[0021]

[Effect of the idea]

As described above, according to this invention, the bearing that supports the rotating shaft is made of an elastic material or Since it is fixed to the main body through a hard vibration isolating material, it is difficult to switch the armature. The vibration of the rotor caused by this is absorbed by this elastic body or vibration isolating material made of low hardness As a result, the vibrations of the rotor are not transmitted to the body, which causes the rotor and body to It is possible to eliminate the resonance sound that occurs during the process and prevent the occurrence of abnormal noise.

[0022] Also, in cases where the rotating shaft rotates and its position shifts due to centrifugal force, etc. Also, the vibration isolating material made of an elastic body or low hardness material returns the rotating shaft to its original position due to its elastic force. This action allows the rotating shaft to self-align, preventing shaft shifting and bearing seizure. It is possible to prevent such problems and maintain the rotor position with high accuracy. For example, even if an external force is applied to the rotor from the outside, the external force is Since it is absorbed by the vibration isolating material made of low hardness material, it prevents deformation of the inner surface of the bearing and the rotating shaft. I can do it.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a brushless motor according to a first embodiment of the invention.

FIG. 2 is a sectional view of a brushless motor according to a second embodiment of the invention.

[Explanation of symbols]

1 Brushless motor 2 Main body 3 Rotor 4 Printed circuit board 5 Rotating shafts 10a, 10b, 20a, 20b Bearings 11, 17, 21, 22 Vibration isolating material 15 Field magnet 18 Drive coil

Claims (1)

[Scope of utility model registration request] 1. A brushless motor comprising: a rotor that is rotatably provided with a field magnet; an armature that generates a rotating magnetic field with respect to the rotor; and excitation means that excites the armature. A bearing structure for a brushless motor, characterized in that a bearing of a rotating shaft that rotatably supports the rotor is fixed to the main body via an elastic body or a vibration isolating material made of a low hardness material.