JP3517763B2 - Brushless motor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brushless motor mainly used for a blower of a vehicle air conditioner.

[0002]

2. Description of the Related Art As a conventional brushless motor disclosed in, for example, Japanese Utility Model Laid-Open No. 3-48339, an end of an exciting coil wound around a stator is excited by an exciting current for exciting the exciting coil. The circuit is directly connected to the wired control board. Further, when the tip of the exciting coil wound around the stator is directly connected to the control board, the exciting coil has an indeterminate shape, so that workability is poor and it is not suitable for automation. Therefore, generally, the tip of the exciting coil is fixed to a relatively rigid terminal, and the terminal and the control board are connected to solve the above problem.

[0003]

However, the vibration of the stator caused by the reaction force when the rotor rotates is
When it is transmitted to the joint between the terminal and the control board, fatigue failure occurs at the joint, causing a problem of electrical disconnection, and vibration transmitted to the control board through the terminal causes noise. There is also a problem.

Therefore, an object of the present invention is to prevent the vibration of the stator from propagating, prevent the fatigue destruction of the terminals of the control board, and reduce the noise.

[0005]

Therefore, according to the present invention, there is provided a rotating shaft, a rotor fixed to the rotating shaft, a permanent magnet annularly arranged on the rotor, and a rotating magnetic field with respect to the permanent magnet. In a brushless motor comprising: a stator for generating a magnet, an exciting coil wound around the stator, a control board to which a drive circuit for energizing the exciting coil is wired, and a case housing in which the control board is housed. An intermediate terminal , which is connected to an end of the exciting coil and extends on the control board, and an output terminal of the drive circuit extending on the control board, which is formed in a plate shape by a conductive member. It is to bridge in (Claim 1).

[0006] In this way, it is connected to the excitation coil, before
An input terminal extending on the control board, and the control board of the drive circuit wired to the control board
The output terminal extending upward is formed into a plate shape by a conductive member.
By bridging by the formed intermediate terminal, the vibration of the stator transmitted through the input terminal of the exciting coil can be absorbed by the intermediate terminal, and since the intermediate terminal is not in contact with the control board, Vibration can be prevented from being transmitted to the control board, and the above-mentioned problems can be achieved.

Further, the an intermediate terminal, by the bent portion which is bent in a U-shape Ru at least one formed between said input terminal and said output terminal, stearyl - possible to efficiently absorb the vibrations of motor You can

Further, since the legs of the stator core holder for fixing the stator and the case housing are sandwiched by the elastic members, the vibration of the stator can be prevented from propagating to the case housing.

Further, the leg portions of the stator core holder are provided with air holes to radiate heat generated in the stator.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

The brushless motor 1 shown in FIGS. 1 to 3 is used, for example, as a blower of an air conditioner for a vehicle. A sirocco type fan 4 is fixed to a mounting portion 3 formed at the upper end of a rotary shaft 2. To be done. A rotor (rotor) 5 is press-fitted and fixed near the lower part of the mounting portion 3, and a thrust stopper 6 is press-fitted and fixed below the rotor 5 to support the rotor 5 in the axial direction. .

The rotor 5 has a boss portion 7 press-fitted and fixed to the rotary shaft 2, an umbrella portion 9 extending from the boss portion 7 in an umbrella shape and having a plurality of ventilation holes 8, and the umbrella portion 9. The cylindrical portion 10 extending downward from the outermost peripheral edge, and the cylindrical portion 10
And a plurality of permanent magnets 11 arranged on the inner peripheral side surface of the.

The rotating shaft 2 is rotatably held by bearings 16 and 17. Further, the bearings 16 and 17 are mounted on a through hole 13 formed through a center of a stator (stator) 12 described below, and upper and lower bearing holders 14 and 15 are mounted.
Is stuck to. At the lower end of the rotating shaft 2, a sensor magnet 18 indicating the position of the permanent magnet 11 of the rotor 5 is provided.
Is press-fitted and held by the push nut 79 in the axial direction of the rotary shaft 2, and the distance between the sensor magnet 18 and the plurality of Hall elements 20 mounted on the control board 19 is kept constant.

The sensor magnet 18 is attached to the rotary shaft 2 through the opening 21 formed in the control board 19, and the flange portion 22 formed at the end of the sensor magnet 18 is located below the control board 19. A plurality of Hall elements 20 are formed so as to spread in the radial direction and are located on the back side of the control board 19 and at positions facing the flange portion 22.

Further, these Hall elements 20 accurately detect the position of the permanent magnet 11 of the rotor 5 by detecting the magnetism of the sensor magnet 18, and are arranged on the control board 19 based on the detection result. A rotating magnetic field is generated in the stator 12 by the exciting circuit. A washer group 23 composed of a plurality of washers is interposed between the sensor magnet 18 and the bearing 17 to reduce sliding resistance between the sensor magnet 18 and the bearing.

The stator 12 includes a stator core 35 made of an iron core formed by stacking silicon steel plates in multiple stages, an upper insulating cover 36 mounted so as to sandwich the stator core 35 from above and below, and a lower insulating cover (stator core holding member). Tool 37, an upper insulating cover 36, and an exciting coil 38 wound around the stator core 35 insulated by the stator core holder 37. The stator core 35 has a through hole 13 in which the bearing holders 14 and 15 are mounted, and the peripheral wall 3 of the through hole 13 is formed.
It has a coil winding portion 40 extending from 9 to 6 directions, and an arc-shaped magnetic pole surface 41 facing the permanent magnet 11 of the rotor 5 is formed at the tip of the coil winding portion 40. still,
In this embodiment, the exciting coil 38 is delta-connected.

In the brushless motor 1 having the above-described structure, the position of the sensor magnet 18 detected by the excitation circuit arranged on the control board 19 through the Hall element 20, that is, the position of the so-called permanent magnet 11 of the rotor 5. In order to generate an appropriate rotating magnetic field in the stator 12, the rotor 5 can be rotated.

The case housing 45 is made up of the upper case member 4
6, the lower case member 50, and the lid 47, and the control board 19 is disposed inside. The upper case member 46 has mounting portions 52, 5 in which screw holes 51 for mounting the brushless motor 1 are formed.
3, 54 and a plurality of field effect transistors (FETs) 55 mounted on the control board 19 are provided with an opening 57 on the outside of the fan 4, which exposes a heat sink 56. As a result, the heat radiation plate 56 can be efficiently cooled by the air blown from the fan 4.

The upper surface of the case housing 45 is an inclined surface that gradually inclines downward from the insertion opening 47a formed in the lid 47 through which the stator 12 is inserted to the outer peripheral portion of the upper case member 46. The water droplets attached to the upper surface of the case housing 45 flow outward.

Further, on the side of the case housing 45,
A side portion of the upper case member 46 and a side portion of the lower case member 50 define a connector mounting portion 58 to which a power connector (not shown) is mounted. The connector mounting portion 58 is
It is formed by a plurality of upper guide ribs 59 and a pair of both side guide ribs 60 formed on the side of the upper case member 46, and a connector mounting hole 61 formed on the side of the lower case member 50. A plurality of terminals 62 connected to the control board 19 are projected. Thus, when the power supply connector is mounted on the connector mounting portion 58, the upper guide rib 59 and the both side guide ribs 60 can limit the positions of the power supply connector on the upper side and both sides, which facilitates the mounting work.

The thrust stopper 6 is the rotor 5
And a washer 24 made of NBR rubber and a nylon-based washer 24 between the bearing 16 and the bearing 16.
5, the sliding resistance of the thrust stopper 6 is reduced. The thrust stopper 6 has a through hole 26 through which the rotary shaft 2 is inserted, and a cylindrical portion 27 in which the through hole 26 is formed. The cylindrical portion 27 includes the upper end of the cylindrical portion 27 and the rotor. A peripheral wall 29 is formed that extends in the radial direction along the umbrella portion 15 of No. 5 and extends downward from this peripheral edge with a predetermined width. Further, on the lower end surface of the cylindrical portion 27, an oil guide 30 is formed, which gradually inclines downward from the sliding contact surface with the washer 25 outward in the radial direction. The thrust stopper side opening (upper opening end) 32 of the upper bearing holder 14 is mounted between the radially outer end of the oil guide 30 and the inner side surface of the peripheral wall 29 so as to enter a predetermined distance. There is.

A bearing 16 made of a sintered metal is provided on the bearing holder 14 by a bearing stopper 33.
The felt 34 for supplying lubricating oil is fixed to the bearing 16.

With the above construction, since the diameter of the circle formed by connecting the sides of the vent hole 8 located radially inward is set to be larger than the diameter of the thrust stopper 6, dust entering from the vent hole 8 Is blocked by the thrust stopper 6, the bearing 16 or the bearing 16 and the rotating shaft 2
Will not adhere to the sliding parts of. Furthermore, since the upper opening end 32 of the upper bearing holder 14 is set to enter the annular recess of the thrust stopper 6 by a predetermined distance, dust is introduced into the bearing 16 or the sliding portion between the bearing 16 and the rotary shaft 2. You can be isolated from the path.

The washer group 23 arranged between the bearing 17 and the sensor magnet 18 is made of a synthetic resin, particularly a nylon-based washer (nylon washer) and synthetic rubber, especially NBR (butadiene acrylonitrile rubber). Washer (rubber washer) consisting of
Washers (PO) made of OM (polyoxymethylene) material
M washers), which are sequentially arranged from the bearing 17 side.

Usually, the washer group 23 is arranged between the bearing 17 and the sensor magnet 18 in a state where no special pressure is applied in the axial direction, and the bearing 17 which is stationary and the sensor magnet 18 which rotates. The rotation of the sensor magnet 18 is absorbed so that the gap between them becomes smooth, and the slidability between the end portion of the bearing 17 and the end portion of the sensor magnet 18 is enhanced.

In the brushless motor 1 having the above structure,
The inside and outside insertion portions of the case housing 45 are between the bearing holding portion 15b of the lower bearing holder 15 and the bearing holder holding hole 46a formed in the upper case member 46, and the heat dissipation plate 56 and the upper case member. Opening 5 at 46
7, and this insertion site is sealed in the method described below.

The heat sink 56 is composed of a plurality of the FETs 55.
Abutting part 5 for applying silicone oil to the back surface of the abutment to abut
6a and a plurality of leaf springs 82 for pressing these FETs 55
A leaf spring holding portion 56c into which one end of the fin is inserted, a fin portion 56d exposed from the opening 57, and the fin portion 56.
and a flange portion 56b extending to the peripheral edge of d. Further, the fins 56e and 56f located at both ends of the fin portion 56d are formed with guide portions 56g that are inclined from the outer side to the tip end so that the fins 56e and 56f can be easily inserted into the opening 57.

Normally, the case housing 45 and the bearing holder 15 are made of resin, especially PP (polypropylene), so that the surfaces are ample and the sealing material does not adhere easily, so that the sealing performance can be easily secured. There wasn't. Therefore, in the present invention, first, the insertion portion, the lower surface 15b of the flange portion 15a of the bearing holder and the upper case member 4 are inserted.
The portion of 6 facing the lower side surface 15b and the portion of the heat dissipation plate 46 facing the flange portion 56b are subjected to ultraviolet cleaning (UV cleaning) to appropriately roughen the surfaces of these portions (insertion portions). After that, the parts are assembled by interposing the sealing materials 80 and 81 in the insertion parts, and the sealing of the respective insertion parts is completed by solidifying the sealing material.

Further, as shown in FIGS. 1 and 4, the lower bearing holder 15 has a flange portion 15a extending in the radial direction.
Then, a substantially triangular bearing holding portion 15b extending axially from the flange portion 15a and fitted into a bearing holder holding hole 46a opening in the upper case member 46 of the case housing 45 is formed. Incidentally, 71 is a lower bearing stopper.

The input terminal 73 to which the end of the exciting coil 38 is fixed is fixed to the stator core holder 37 and the flange portion 15 of the bearing holder 15 below.
It penetrates through a, passes through a through hole 90 formed in the control board 19, and extends to the lower side of the control board 19. The output terminal 75 of the drive circuit wired to the control board 19 also penetrates the control board and extends downward to the control board. The input terminal 73 and the output terminal 75 are connected to the control board 1
It is bridged by an intermediate terminal 74 which is arranged so as to float from 9. The intermediate terminal 74 is formed in a plate shape by a conductive member such as soft iron that does not easily transmit vibration, and absorbs the vibration of the stator 12 transmitted through the input terminal 73. Further, in this embodiment, the vibration is further absorbed by forming the U-shaped bent portion 74a.

As shown in FIGS. 4 and 61 (a) and 61 (b), the stator core holder 37 has a leg portion 42 extending in six directions, and a tip end portion 42c of the leg portion 42 is It is sandwiched between the annular elastic members 43 and 44, further sandwiched between the upper case member 46 forming the case housing 45 and the lid 47, and fixed to the case housing 45. Accordingly, the vibration of the stator 12 caused by the reaction force due to the rotation of the rotor can be absorbed by the elastic members 43 and 44, so that the noise leaking from the case housing can be suppressed.

In this embodiment, as shown in FIG. 6, the tip portions 42c of the alternate leg portions 42 are
A protrusion 42a that meshes with the annular elastic member 44 is formed. Further, an opening 42b is formed in the leg portion 42 so that the temperature rise of the stator 15 can be suppressed. In FIG. 6, reference numeral 42d is a holding wall portion that holds the end portion of the elastic member 43, and 42f is an insertion portion into which the coil winding portion 40 of the stator core 35 is inserted.

Further, in this embodiment, the stator core holder 37 has a specific gravity of 1.22 to 1.33, a tensile strength of 30 to 40 MPa, a tensile elongation of 200% or more, and a bending elastic modulus of 1.8 to 2.8 GPa. , Bending strength 60 ~
By forming a material such as a synthetic resin defined at 85 MPa, magnetic vibration due to torque ripple can be reduced.

[0034]

As described above, according to the present invention, it is connected to the exciting coil and is mounted on the control board.
The input terminal extending and the output terminal extending on the control board of the drive circuit wired to the control board are bridged by an intermediate terminal formed in a plate shape by a conductive member , whereby the exciting coil The vibration of the stator transmitted through the input terminal can be absorbed by the intermediate terminal, and since the intermediate terminal is not in contact with the control board, it is possible to prevent the vibration from being transmitted to the control board. It is possible to prevent noise and prevent fatigue damage of each contact of the control board.

[Brief description of drawings]

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

FIG. 2 is a side view of the brushless motor according to the present invention.

FIG. 3 is a plan view of the brushless motor according to the present invention.

FIG. 4 is a bottom view of the stator.

FIG. 5 is a bottom view of the brushless motor according to the present invention with a lower case member removed.

FIG. 6A is a plan view of a stator core holder, and FIG.
Is a front view.

[Explanation of symbols]

1 brushless motor 2 rotation axes 5 rotor 12 stator 19 Control board 35 Stator core 37 Stator core holder 73 Input terminal 74 Intermediate terminal 75 Output terminal

Front page continued (72) Inventor Masami Takemasa 39, Toyo, Konan-cho, Osa-gun, Saitama Prefecture, Chiba, East District 39 XXcel Co., Ltd. in the Konan Factory (72) Tatsuo Haraguchi, Otsu-gun, Konan-cho, Saitama Prefecture 39, Yoyohara XXcel Co., Ltd. in the Gangnam factory (72) Inventor Kaei Gunji 39 Toji, Toyo, Konan-cho, Osa-gun, Saitama-prefecture ZEXcel Co., Ltd. in the Konan factory (72) Hiroshi Osawa, Chiyo-ji, Konan-cho, Oza-gun, Saitama Address 39 XXCEL Co., Ltd. in the Gangnam Factory (56) Reference JP-A-7-59327 (JP, A) JP-A-5-115144 (JP, A) JP-A-61-99283 (JP, A) 57-181016 (JP, U) Actual development 63-75929 (JP, U) (58) Fields surveyed (Int.Cl. ⁷ , DB name) H02K 29/00 H02K 3/18 H02K 3/46 H02K 5 / 24 H02K 21/00

Claims (2)

(57) [Claims] 1. A rotating shaft, a rotor fixed to the rotating shaft, a permanent magnet annularly arranged on the rotor, a stator for generating a rotating magnetic field for the permanent magnet, and a winding on the stator. An exciting coil that is rotated, and a control board to which a drive circuit that energizes the exciting coil is wired,
A brushless motor including a case housing in which the control board is housed , the control base being connected to an end of the exciting coil.
The input terminal extending on the board and the control board
The extended output terminal of the drive circuit is connected by a conductive member.
A brushless motor characterized by being bridged by an intermediate terminal formed in a plate shape . The method according to claim 2, wherein the intermediate terminal, the brushless motor according to claim 1, wherein the bent portion is bent in a U shape between said input terminal and said output terminal, characterized in that that will be at least one form.