Fan Motor and Electronic Device Comprising the Same

Abstract

A fan motor and an electric device having the same are disposed. The fan motor and the electronic device having the same are provided with: a stator part including a coil and a stator yoke provided at a lower part of the coil; a rotor part including a magnet spaced apart from an upper surface of a stator yoke and a back yoke tightly provided on the upper surface of the magnet; a fan member including a rotating shaft which rotates to become a rotation center of the rotor part, and a plurality of impellers to which the magnet is fixedly coupled on inner circumferential surfaces of the impellers; a body part accommodating the stator part; and a cover part having an intake hole and an exhaust hole, and provided at an upper end part of the body part to accommodate the plurality of impellers.

Description

CROSS REFERENCE TO RELATED APPLICATION

[0001] The present application claims priority to Korean Patent Application No. 10-2019-0005000, filed Jan. 15, 2019, the entire contents of which is incorporated herein for all purposes by this reference.

BACKGROUND OF THE INVENTION

Field of the Invention

[0002] The present invention relates to a fan motor that is applied to a kind of sensor module that detects temperature, humidity, and a dust turbidity state of indoor air of a vehicle, and further controls the operation of an air cleaner of the vehicle. More particularly, the present invention relates to a fan motor and an electronic device having the same, the fan motor including: a stator part including a coil and a stator yoke provided at a lower part of the coil; a rotor part including a magnet spaced apart from an upper surface of the stator yoke and a back yoke tightly provided on the upper surface of the magnet; a fan member including a rotating shaft which rotates to become a rotation center of the rotor part, and a plurality of impellers to which the magnet is fixedly coupled on inner circumferential surfaces of the impellers; a body part accommodating the stator part; and a cover part having an intake hole and an exhaust hole, and provided at an upper end part of the body part to accommodate the plurality of impellers, wherein the stator yoke is seated in a groove part provided in the bottom surface of the body part as a plate-shaped member, the groove part is provided with a bearing housing for shaft-supporting a sleeve bearing elongated for rotationally supporting the rotating shaft, and the bearing housing is provided by protruding integrally with the body part in the central part where the groove part is provided, and thus the fan motor not only prevents the axial deviation of the sleeve bearing, but also solves the problem of an impact-loaded friction joint between the sleeve bearing and the rotating shaft, which is generated during rotation, to increase operation life, and to facilitate easy quality control.

Description of the Related Art

[0003] The fan motor generally includes a motor that converts electrical energy into mechanical energy, such as rotational force, and the fan motor may classified into an outer rotor type fan motor, an inner rotor type fan motor, and a flat type fan motor, depending on whether a rotor is disposed outside or inside a stator. Also, the fan motor has a structure in which a magnet and a coil are arranged in a vertical direction, and the electromagnetic force flows sequentially to an edge part of the coil so that the magnet is rotated by the electromagnetic force.

[0004] The above mentioned fan motor removes a brush and a commutator from a direct current (DC) motor, is provided with a multipole magnet rotor, and employs a brushless motor that generates a rotating magnetic field by providing a driving coil at a position around the magnet rotor so as to drive the magnet rotor.

[0005] The brushless fan motor uses a sleeve bearing that is elongated to rotationally support the rotating shaft in order to smoothly rotate the rotating shaft of the motor. However, the fan motor using such a sleeve bearing has the problems in that the sleeve bearing may be separated or an intermetallic friction joint may occur between the sleeve bearing and the rotating shaft when the motor is driven.

[0006] Regarding the brushless fan motor as described above, Korean Patent No. 10-1828065 and Korean Patent Application Publication No. 10-2018-0125132 are proposed.

SUMMARY OF THE INVENTION

[0007] The present invention has been devised and developed to solve the problems of the related art as described above, and an objective thereof is to provide a fan motor and an electronic device including the same, the fan motor including: a stator part including a coil and a stator yoke provided at a lower part of the coil; a rotor part including a magnet spaced apart from an upper surface of the stator yoke and a back yoke tightly provided on the upper surface of the magnet; a fan member including a rotating shaft which rotates to become a rotation center of the rotor part, and a plurality of impellers to which the magnet is fixedly coupled on inner circumferential surfaces of the impellers; a body part accommodating the stator part; and a cover part having an intake hole and an exhaust hole, and provided at an upper end part of the body part to accommodate the plurality of impellers, wherein the stator yoke is seated in a groove part provided in the bottom surface of the body part as a plate-shaped member, the groove part is provided with a bearing housing for shaft-supporting the sleeve bearing elongated for rotationally supporting the rotating shaft, and the bearing housing is provided by protruding integrally with the body part in the central part where the groove part is provided, and thus the present invention not only prevents the axial deviation of a sleeve bearing, but also solves the problem of the impact-loaded friction joint between the sleeve bearing and the rotating shaft, which is generated during rotation, to increase operation life, and to facilitate easy quality control.

[0008] In order to achieve the objective of the present invention, there is provided a fan motor including: a stator part including a coil and a stator yoke provided at a lower part of the coil; a rotor part including a magnet spaced apart from an upper surface of the stator yoke and a back yoke tightly provided on an upper surface of the magnet; a fan member including a rotating shaft which rotates to become a rotation center of the rotor part, and a plurality of impellers to which the magnet is fixedly coupled on inner circumferential surfaces of the impellers; a body part accommodating the stator part; and a cover part having an intake hole and an exhaust hole, and provided at an upper end part of the body part to accommodate the plurality of impellers, wherein the stator yoke is seated in a groove part provided in a bottom surface of the body part as a plate-shaped member, the groove part is provided with a bearing housing for shaft-supporting a sleeve bearing elongated for rotationally supporting the rotating shaft, and the bearing housing is provided by protruding integrally with the body part in a central part where the groove part is provided.

[0009] In addition, in the present invention, a circuit board for driving the stator part may be disposed at a position between the stator yoke and the magnet.

[0010] In addition, in the present invention, an end part of the bearing housing may be provided with a bearing support part provided as an inner circumferential surface of the bearing housing to prevent the sleeve bearing from separation.

[0011] In addition, in the present invention, the bearing support part may prevent a bearing from separation by fixing the bearing through insert injection molding, at least one caulking, or heat welding.

[0012] In addition, in the present invention, the fan motor may further include a separation prevention member provided at a position between the bearing support and the bearing.

[0013] In addition, in the present invention, the bearing housing may be provided with a stopper part for matching centers of gravity of the rotor part and the sleeve bearing.

[0014] In addition, in the present invention, the bearing housing may be simultaneously accommodated inside the stator part, inside the rotor part, and inside the circuit board.

[0015] In addition, in the present invention, the stator yoke may be provided at a position in the groove part of the body part, and is fixed by insert injection molding or heat welding.

[0016] In addition, in the present invention, the stator yoke may have a polygonal shape.

[0017] In addition, in the present invention, the coil of the stator part may be a hollow coil, having a square shape.

[0018] In addition, in the present invention, an electric device includes a fan motor including the above configuration.

[0019] The fan motor according to the present invention is effective in that the fan motor includes: a stator part including a coil and a stator yoke provided at a lower part of the coil; the rotor part including a magnet spaced apart from an upper surface of a stator yoke and a back yoke tightly provided on the upper surface of the magnet; a fan member including a rotating shaft which rotates to become a rotation center of the rotor part, and a plurality of impellers to which the magnet is fixedly coupled on inner circumferential surfaces of the impellers; a body part accommodating the stator part; and a cover part having an intake hole and an exhaust hole, and provided at an upper end part of the body part to accommodate the plurality of impellers, wherein the stator yoke is seated in a groove part provided in the bottom surface of the body part as a plate-shaped member, the groove part is provided with a bearing housing for shaft-supporting the sleeve bearing elongated for rotationally supporting the rotating shaft, and the bearing housing is provided by protruding integrally with the body part in the central part where the groove part is provided, and thus the fan motor not only prevents the axial deviation of a sleeve bearing, but also solves the problem of the impact-loaded friction joint between the sleeve bearing and the rotating shaft, which is generated during rotation, to increase operation life, and to facilitate easy quality control.

[0020] In addition, the present invention reduces the lengths of the rotating shaft and of the sleeve bearing to match the center of gravity with the fan member, and changes a production method of the bearing support part from the press to the injection molding. Accordingly, the present invention suppresses occurrence of the impact-loaded friction joint between the sleeve bearing and the rotating shaft, which is generated when the motor rotates, thereby not only increasing the operation life, but also facilitating quality control.

[0021] In addition, the present invention provides the stator yoke in a polygon shape so that each vertex of the polygon of the stator yoke is coincident with the center point of each of the N pole and the S pole of the multipole magnetized magnet. Therefore, the starting position of the rotor part is determined, so it is possible to eliminate the magnet for sensing.

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] FIG. 1 is an exploded perspective view of a fan motor according to the present invention.

[0023] FIG. 2 is a perspective view of a state in which the fan motor is a completed assembly according to the present invention.

[0024] FIG. 3 is a cross-sectional view of FIG. 2.

[0025] FIG. 4 is a detailed cross-sectional view around the fan member in the fan motor according to the present invention.

[0026] FIG. 5A is an exploded view of the fan member, and FIG. 5B is a perspective view of the fan member which is a completed assembly.

[0027] FIG. 6 is a coupled perspective view of the fan member and the body part in the present invention.

[0028] FIG. 7 is a detailed view of the body part.

[0029] FIG. 8 is a partial detail view of the body part.

[0030] FIG. 9A is a view showing a state without caulking on the upper part of a sleeve bearing, and FIG. 9B is a view showing a state with caulking on the upper part of the sleeve bearing.

[0031] FIG. 10 is a cross-sectional view of FIG. 9B.

[0032] FIG. 11 is a view showing another exemplary embodiment for preventing the sleeve bearing from separation.

DETAILED DESCRIPTION OF THE INVENTION

[0033] The present invention relates to a fan motor that is applied to a kind of sensor module that detects temperature, humidity, and a dust turbidity state of indoor air of a vehicle, and further operates to control driving of an air cleaner. Hereinafter, the fan motor will be described in detail with reference to the accompanying drawings.

[0034] As shown in FIGS. 1 to 4, the fan motor according to the present invention includes: a cover part 10 having an intake hole 11 and an exhaust hole 12; a fan member 20 accommodated in a fan member accommodating part 13 provided inside the cover part 10 to include a rotating shaft 32 that rotates to become the rotation center of a rotor part, and provided with the plurality of impellers to which a magnet 33 is fixedly coupled on the inner circumferential surfaces of the impellers 22; a stator part including a coil 51 wound around a driving coil and a stator yoke 52 disposed at a position below the coil 51; the rotor part including the magnet 33 spaced apart from an upper surface of the stator yoke 52, and a back yoke 31 tightly provided on the upper surface of the magnet 33; a circuit board 40 generating driving power and a control signal to the coil 51 to drive the stator part; and a body part 70 provided at a lower part of the cover part 10 to accommodate the stator part.

[0035] As shown in FIG. 2, the cover part 10 is provided with the intake hole 11 and the exhaust hole 12 to help intake and exhaust air through a swirl chamber when the rotor part rotates.

[0036] As shown in FIGS. 5A and 5B, the fan member 20 includes: a fan member body 21 having an accommodating space 24 formed at a lower part thereof, in which the back yoke 31 and the magnet 33 are fixedly coupled to the accommodating space 24; a plurality of impellers 22 integrally provided on an upper part of the fan member body 21; and a rotating shaft coupling part 23 fixedly coupled to an upper end part of the rotating shaft 32.

[0037] The stator part is composed of the coil 51 wound around the driving coil and the stator yoke 52 provided at a lower part of the coil 51 and others. Without having a separate bobbin, the coil 51 practically has a rectangular shape instead of a circular shape in order to use the electromagnetic force generated from the edge part of the coil 51 when power is applied to a hollow coil. The hollow coil is provided on the lower part surface of a through part of the circuit board 40, and is disposed between the stator yoke 52 and the circuit board 40.

[0038] The rotor part is composed of the magnet 33 spaced apart from an upper surface of the stator yoke 52, and the back yoke 31 tightly provided on the upper surface of the magnet 33. The rotor part has a structure in which the fan member 20 fixedly coupled to the upper end of the rotating shaft 32 rotates in accordance with the rotating shaft rotating when driving power is supplied to the stator part.

[0039] A cap-shaped bearing housing 60 capable of accommodating a sleeve bearing 53 seated on the upper part of the body part 70 is integrally protruded from the body part 70 and, particularly from the central part of a groove part in which the stator yoke 52 is accommodated. The flat plate-shaped stator yoke 52 is mounted on the bottom of the bearing housing 60 so as to be integrally provided at the bottom of the body part 70 by means of insert injection molding or heat welding.

[0040] As shown in FIGS. 8 to 10 with respect to the end part of the bearing housing 60, an incised V-shape bearing support part is provided as an inner circumferential surface of the bearing housing in order to prevent the sleeve bearing 53 from separation. The bearing support part 62 prevents the press-fitted sleeve bearing 53 from separation, by way of fixing the sleeve bearing 53 through the insert injection molding, forming at least one caulking part 63 in which a part of the inner circumferential surface is cut inward, or fixing the upper end of the sleeve bearing 53 by the heat welding.

[0041] In addition, as shown in FIG. 11, in order to reduce the gap between the upper surface of the sleeve bearing 53 and the bearing support part 62, a separation prevention member 65 such as a washer may be further provided between the bearing support part 62 and the sleeve bearing 53. In this case, the bearing support part 62 may be fixed by the insert injection molding, caulking, or the heat welding to further prevent the sleeve bearing 53 from separation.

[0042] The centers of gravity of the rotor part and of the sleeve bearing 53 may be matched by reducing the lengths of the rotating shaft 32 and of the sleeve bearing 53 so as to reduce shaking during the rotation of the rotating shaft 32, thereby reducing the friction joint. In addition, the material of the bearing support part 62 may be changed to plastic injection material so as to reduce the friction joint between the rotating shaft 32 and the sleeve bearing 53. In order to match the centers of gravity of the rotor part and the sleeve bearing 53 as described above, a mounting height of the sleeve bearing 53 is needed to be limited. Therefore, a stopper part 64 which limits the mounting height of the sleeve bearing 53 is provided in the bearing housing 60. In other words, the present invention is devised such that the centers of gravity of the rotor part and the sleeve bearing 53 is checked in 3D stereoscopic way, so that one end part out of two end parts inside the bearing housing plays a role as a stopper on the actual product. By reducing the lengths of the rotating shaft 32 and of the sleeve bearing 53 as described above to match the centers of gravity of the rotor part and the sleeve bearing 53, and by changing a production method of the bearing support part 62 to the injection molding, there is an effect that the friction joint may be maximally reduced in comparison with the conventional structure supporting the rotating shaft 32 and the sleeve bearing 53 long in the vertical direction. As an example, the stopper part 64 is experimentally provided at a position of 1 mm.+-.0.05 from the lower end part of the rotating shaft 32. In this case, the sleeve bearing 53 practically has a length of 5 mm.+-.0.1.

[0043] As shown in FIG. 6, the bearing housing 60 is simultaneously accommodated inside the stator part, inside the rotor part, and inside the circuit board 40.

[0044] In addition, the sleeve bearing 53 is mounted so that the centers of gravity of the sleeve bearing 53 and the rotor part having the fan member 20 coincide with each other. Accordingly, the sleeve bearing 53 in the bearing housing 60 is provided to be accommodated in the fan member 20.

[0045] The stator yoke 52, which is a plate-shape member, as shown in FIGS. 7 and 8, is seated in the groove part 72 provided in the bottom surface 71 of the body part 70. The groove part 72 is provided with the bearing housing 60 for axially supporting the elongated sleeve bearing 53 rotationally supporting the rotating shaft 32. The bearing housing 60 protrudes integrally with the body part 70 at a central part in which the groove part 72 is provided. The stator yoke 53 is practically provided in the groove part 72 of the body part 70 to be fixed by insert injection molding or heat welding.

[0046] In addition, it is assumed that the stator yoke 52 has a polygonal shape. By providing the stator yoke 52 in the polygon shape, each vertex of the polygon of the stator yoke 52 coincides with the center point of each N pole and S pole of the multipole magnetized magnet 33. Consequently, the starting position of the rotor part is determined, so it is possible to eliminate the magnet for sensing.

[0047] Although the fan motor applied to the sensor module for the vehicle is described above, the present invention is also applicable to the electronic device to which the fan motor having the above structure is applied.

[0048] In addition, as described above, the present invention has been described with reference to the practical exemplary embodiments. However, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the present invention as disclosed in the accompanying claims.

Claims

1. A fan motor comprising: a stator part comprising a coil and a stator yoke provided at a lower part of the coil; a rotor part comprising a magnet spaced apart from an upper surface of the stator yoke and a back yoke tightly provided on an upper surface of the magnet; a fan member comprising a rotating shaft which rotates to become a rotation center of the rotor part, and a plurality of impellers to which the magnet is fixedly coupled on inner circumferential surfaces of the impellers; a body part accommodating the stator part; and a cover part having an intake hole and an exhaust hole, and provided at an upper end part of the body part to accommodate the plurality of impellers, wherein the stator yoke is seated in a groove part provided in a bottom surface of the body part as a plate-shaped member, the groove part is provided with a bearing housing for shaft-supporting a sleeve bearing elongated for rotationally supporting the rotating shaft, and the bearing housing is provided by protruding integrally with the body part in a central part where the groove part is provided.

2. The fan motor of claim 1, wherein a circuit board for driving the stator part is disposed at a position between the stator yoke and the magnet.

3. The fan motor of claim 1, wherein an end part of the bearing housing is provided with a bearing support part provided as an inner circumferential surface of the bearing housing to prevent the sleeve bearing from separation.

4. The fan motor of claim 3, wherein the bearing support part prevents a bearing from separation by fixing the bearing through insert injection molding, at least one caulking, or heat welding.

5. The fan motor of claim 4, further comprising: a separation prevention member provided at a position between the bearing support and the bearing.

6. The fan motor of claim 1, wherein the bearing housing is provided with a stopper part for matching centers of gravity of the rotor part and the sleeve bearing.

7. The fan motor of claim 2, wherein the bearing housing is simultaneously accommodated inside the stator part, inside the rotor part, and inside the circuit board.

8. The fan motor of claim 1, wherein the stator yoke is provided at a position in the groove part of the body part, and is fixed by insert injection molding or heat welding.

9. The fan motor of claim 1, wherein the stator yoke has a polygonal shape.

10. The fan motor of claim 1, wherein the coil of the stator part is a hollow coil, having a square shape.

11. (canceled)

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