JP2023008822A - waterproof fan - Google Patents

Abstract

To provide a waterproof fan which prevents water from entering a circuit board even when heat stress repeatedly acts thereon.SOLUTION: A waterproof fan includes a rotor 2 having a rotation shaft part and a rotary vane rotatable around a rotation axial line X, a stator 3, a circuit board 7, a resin-made frame 6 having a storage space 64 for storing a circuit board 7, a waterproof resin part 8 which covers the stator 3 and blocks an opening of the storage space 64, a bearing 4 rotatably supporting the rotation shaft part around a rotation axial line X, and a metal-made bearing holder 5 which extends in the rotation axial line X, has a cylindrical shape and supports the bearing 4. The frame 6 has a cylindrical holder protective part 61 covering at least a part of the outer peripheral surface of the bearing holder 5, and the holder protective part 61 separates the stator 3 from the bearing holder 5.SELECTED DRAWING: Figure 2

Description

The present invention relates to waterproof fans.

2. Description of the Related Art A waterproof fan in which electronic components including a circuit board are covered with resin is known from Patent Document 1 and the like. In the waterproof fan disclosed in Patent Document 1, a bearing that supports a rotor is supported by a metallic bearing-supporting cylindrical portion.

Japanese Patent Application Laid-Open No. 2020-88990

By the way, the waterproof resin that covers the electronic parts (including circuit boards, etc.) has a coefficient of linear expansion that is significantly different from that of the metal that forms the bearing support cylinder. There is a possibility that a gap may be generated at the interface of the support cylinder. Then, there is a possibility that water may enter through this gap.

In such a case, in the waterproof fan described in Patent Literature 1, since the interface between the bearing-supporting cylinder and the waterproof resin is exposed to the outside, the inside of the waterproof fan runs from this interface along the bearing-supporting cylinder. There is a risk that water will enter the circuit board, and the water that has entered may reach the circuit board.

Accordingly, the present invention provides a waterproof fan that prevents water from entering the circuit board even when thermal stress is repeatedly applied.

A waterproof fan according to one aspect of the present invention includes:
a rotor comprising a rotary shaft portion rotatable around a rotary axis and rotary blades;
a stator with windings;
a circuit board that energizes the winding;
a resin frame having a bottom surface positioned on one side of the rotation axis and having an accommodation space that opens to the other side of the rotation axis and accommodates the circuit board;
a waterproof resin part that covers the stator and closes the opening of the accommodation space;
a bearing that supports the rotating shaft portion so as to be rotatable around the rotating axis;
a cylindrical bearing holder that supports the bearing and extends along the axis of rotation;
The frame has a cylindrical holder protection portion that extends from the bottom surface to the other side of the rotation axis and covers at least a portion of the outer peripheral surface of the bearing holder, and the holder protection portion protects the stator from the bearing holder. I keep them apart.

A waterproof fan according to one aspect of the present invention includes:
a rotor comprising a rotary shaft portion rotatable around a rotary axis and rotary blades;
a stator with windings;
a circuit board that energizes the winding;
a resin frame having a bottom surface positioned on one side of the rotation axis and having an accommodation space that opens to the other side of the rotation axis and accommodates the circuit board;
a waterproof resin part that covers the stator and closes the opening of the accommodation space;
a bearing that supports the rotating shaft portion so as to be rotatable around the rotating axis;
a cylindrical bearing holder that supports the bearing and extends along the axis of rotation;
the frame has a cylindrical first holder protection portion that extends from the bottom surface to the other side of the rotation axis and covers a part of the outer peripheral surface of the bearing holder;
A cylindrical second holder protection portion covering the other part of the outer peripheral surface of the bearing holder is provided on the other side of the rotation axis relative to the first holder protection portion,
At least the second holder protection part separates the stator from the bearing holder.

According to the present invention, it is possible to provide a waterproof fan that prevents water from entering the circuit board even when thermal stress is repeatedly applied.

1 is a front view of a waterproof fan according to an embodiment of the present invention; FIG. FIG. 2 is a cross-sectional view of the waterproof fan according to the first embodiment of the present invention, taken along the line AA shown in FIG. 1; FIG. 3 is a view similar to FIG. 2 according to a modification of the first embodiment of the invention; 1 is a perspective view of a frame according to a first embodiment of the invention; FIG. 1 is a top view of a waterproof fan according to a first embodiment of the present invention; FIG. FIG. 2 is a cross-sectional view of the waterproof fan according to the second embodiment of the present invention, taken along the line AA shown in FIG. 1; FIG. 7 is a view similar to FIG. 6 according to a modification of the second embodiment of the invention;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. For the sake of convenience, descriptions of members having the same reference numbers as members already described in the description of the embodiment will be omitted. Also, the dimensions of each member shown in this drawing may differ from the actual dimensions of each member for convenience of explanation.

FIG. 1 is a front view of a waterproof fan 1 according to an embodiment of the invention. As shown in FIG. 1, the waterproof fan 1 includes a plurality of (in the example shown in the figure, seven) rotor blades W rotatable around a rotating shaft portion 20, and a cylindrical fan surrounding the outer periphery of the rotor blades W. a casing C; The waterproof fan 1 generates an air current flowing from one direction of the axis line of the rotating shaft portion 20 (front and back directions in the drawing) to the other direction by the rotation of the rotor blades W. As shown in FIG. In the following description, for the sake of convenience, the direction of the axis of the rotating shaft portion 20 may be referred to as the direction of the "rotational axis X". Also, the direction orthogonal to the rotation axis X is sometimes called the "radial direction".

A plurality of rotor blades W are radially mounted around the impeller boss portion 21 . The impeller boss portion 21 is formed in a substantially cup shape and is provided so as to surround the rotating shaft portion 20 . In addition, in the waterproof fan 1 shown in FIG. 1, the state inside the stator 3 is drawn with a broken line.

The rotor blades W attached to the impeller boss portion 21 generate an airflow between the rotor blades W and the casing C as the rotor blades W rotate. The rotor blade W is formed in a shape and structure that generates an airflow from one side of the rotation axis X to the other side. Further, the casing C surrounding the rotor blades W has a rectangular frame portion 11 and a circular wind tunnel portion 12 defined in the center of the frame portion 11 and guiding the airflow.
(First embodiment)

FIG. 2 is a waterproof fan according to the first embodiment of the present invention, and is a cross-sectional view taken along line AA shown in FIG. In the following description, one side of the rotation axis X may be referred to as the rear B, and the other side opposite to the one side of the rotation axis X may be referred to as the front F for convenience.

As shown in FIG. 2 , waterproof fan 1 includes rotor 2 , stator 3 , bearing 4 , bearing holder 5 , frame 6 , circuit board 7 , and waterproof resin portion 8 . Since the structure of the waterproof fan 1 is symmetrical with respect to the rotation axis X, the upper half of FIG. 2 will be described below.

The rotor 2 includes an impeller boss portion 21 having rotor blades W, a rotor cover 22 provided in the impeller boss portion 21, permanent magnets 23 fixed to the rotor cover 22, and an impeller boss portion 21 and rotor cover 22. and a rotary shaft portion 20 that is press-fitted via a bush (not shown). Note that the rotation shaft portion 20 is omitted in FIG. 2 .

The rotor cover 22 has a substantially cup shape and is fitted in the impeller boss portion 21 . The rotor cover 22 is made of a magnetic material such as carbon steel casting (SC material). Permanent magnets 23 are fixed to the inner circumferential surface of the rotor cover 22 in the radial direction so as to be aligned in the circumferential direction. The rotor cover 22 conducts magnetic flux and becomes part of the magnetic circuit.

The rotating shaft portion 20 is provided rotatably around the rotation axis X. As shown in FIG. The rotating shaft portion 20 is supported by a bearing 4 having a first bearing 4a and a second bearing 4b.

The stator 3 is provided on the rear side B of the rotor 2 . The stator 3 has a plurality of stator cores 31 , windings 32 wound around each of the stator cores 31 , and insulators 33 provided between the stator cores 31 and the windings 32 .

The stator core 31 is arranged radially inside the rotor blades W. As shown in FIG. Each stator core 31 extends radially with respect to the rotation axis X. As shown in FIG. The radial outer surface of the stator core 31 is provided to face the radial inner surface of the permanent magnets 23 fixed to the rotor cover 22 . The stator core 31 is formed by laminating a plurality of thin metal plates in the plate thickness direction. As a material of the stator core 31, for example, a silicon steel plate is used.

Each stator core 31 is fixed to the radially outer side of a holder protection portion 61 (described later) that constitutes the frame 6 via an insulator 33 . The insulator 33 is composed of a front insulator 33A provided on the front F surface of the stator core 31 and a rear insulator 33B provided on the rear B surface of the stator core 31 . The front insulator 33A is provided with a front inner protruding portion and a front outer protruding portion extending forward F. As shown in FIG. A front slot 34A is formed between the front inner protrusion and the front outer protrusion. The rear insulator 33B is provided with a rear inner protruding portion and a rear outer protruding portion extending rearward B. As shown in FIG. A rear slot 34B is formed between the rear inner protrusion and the rear outer protrusion.

Winding 32 is wound around stator core 31 . Windings 32 are accommodated in front slots 34A and rear slots 34B. A front insulator 33 A is provided between the winding 32 and the front surface of the stator core 31 , and a rear insulator 33 B is provided between the winding 32 and the rear surface of the stator core 31 . Therefore, insulation between the windings 32 and the stator core 31 in the direction of the rotation axis X is ensured. Further, when viewed from the direction of the rotation axis X, the shape of the front insulator 33A is larger than the shape of the stator core 31, and the shape of the rear insulator 33B is larger than the shape of the stator core 31. As shown in FIG. Therefore, the winding 32 positioned between the front insulator 33A and the rear insulator 33B is also insulated from the stator core 31 .

The bearing 4 is composed of a first bearing 4a provided in the rear B and a second bearing 4b provided in the front F. The first bearing 4a and the second bearing 4b support the rotating shaft portion 20 so as to be rotatable around the rotation axis X. As shown in FIG.

The bearing holder 5 is a cylindrical holder extending along the rotation axis X. As shown in FIG. The bearing holder 5 is made of metal. A first bearing 4 a and a second bearing 4 b are inserted into the bearing holder 5 . The bearing holder 5 supports the first bearing 4a and the second bearing 4b. The bearing holder 5 includes a first bearing support portion 51 provided at the rear B, a second bearing support portion 52 provided at the front F, and provided between the first bearing support portion 51 and the second bearing support portion 52. and a small diameter portion 53 . The first bearing support portion 51 supports the first bearing 4a. The second bearing support portion 52 supports the second bearing 4b. The small diameter portion 53 is formed to have a smaller diameter than the inner diameter of the first bearing support portion 51 and the inner diameter of the second bearing support portion 52 .

The frame 6 is provided at the rear B position in the construction of the waterproof fan 1 . The frame 6 is generally cup-shaped. The frame 6 is provided along the direction of the rotation axis X with the impeller boss portion 21 to which the rotor blades W are attached and the cup-shaped inner sides facing each other. The frame 6 is made of resin.

The frame 6 includes a holder protection portion 61 provided radially inward, an outer cylindrical portion 62 having a larger diameter than the holder protection portion 61 and provided radially outward, and a holder protection portion 61 provided in the rear B. and a bottom portion 63 that connects with the outer cylinder portion 62 . The frame 6 has a housing space 64 composed of a holder protection portion 61 , an outer cylindrical portion 62 and a bottom portion 63 . The accommodation space 64 is a space that opens forward F. As shown in FIG. The circuit board 7 is accommodated in the accommodation space 64 .

The bottom portion 63 is provided so as to extend radially from the radially outer peripheral surface of the holder protective portion 61 to the radially inner peripheral surface of the outer cylindrical portion 62 . The bottom portion 63 is provided so as to cover the rear portion B of the stator 3 .

The circuit board 7 is provided on the rear side B of the stator 3 . The circuit board 7 is housed in the housing space 64 . The circuit board 7 is formed in a circular donut shape with an opening in the center. The circuit board 7 is provided so that the holder protection portion 61 of the frame 6 is inserted through the opening and the periphery of the holder protection portion 61 is surrounded. The diameter of the opening of the circuit board 7 is sized to provide a predetermined gap between the edge of the opening and the outer peripheral surface of the holder protection portion 61 . A wiring pattern for controlling the rotor 2 and the stator 3 is formed on the circuit board 7 . The circuit board 7 energizes the winding 32 wound around the stator core 31 .

A radial inner end portion of the circuit board 7 is supported by the holder protection portion 61 and the insulator 33 . The circuit board 7 is positioned with respect to the insulator 33 by fitting the end of the circuit board 7 into the notch formed at the tip of the rear B of the insulator 33 . The cutout portion of the insulator 33 is formed only at a part of the distal end portion of the insulator 33 in the circumferential direction. The insulator 33 supports the circuit board 7 only partially in the circumferential direction. The holder protection portion 61 supports the circuit board 7 by a step portion 101c (described later with reference to FIG. 3) provided in the holder protection portion 61. As shown in FIG.

The waterproof resin portion 8 is provided so as to cover the stator 3 and the circuit board 7 . The waterproof resin portion 8 is made of an electrically insulating synthetic resin. For example, the waterproof resin portion 8 is made of thermosetting epoxy resin. The waterproof resin portion 8 closes the opening of the accommodation space 64 by filling the resin so as to cover the stator 3 and the circuit board 7 . The resin of the waterproof resin portion 8 fills, for example, the gap between the stator 3 and the circuit board 7 and the gap between the bottom surface 63 a of the bottom portion 63 of the frame 6 and the circuit board 7 in the accommodation space 64 .

The frame 6 has the holder protection portion 61 as described above. The holder protection portion 61 is a tubular portion continuously extending forward F from the radially inner end portion of the bottom portion 63 . The holder protection portion 61 is inserted through the central portion of the stator 3 . A cylindrical bearing holder 5 is insert-molded in the holder protection portion 61 . The holder protection portion 61 covers at least part of the outer peripheral surface of the bearing holder 5 . Thereby, the holder protection portion 61 separates the stator 3 from the outer peripheral surface of the bearing holder 5 .

A waterproof fan 1 according to the present embodiment includes a rotor 2 having a rotating shaft portion 20 rotatable around a rotation axis X and rotor blades W, a plurality of stator cores 31 extending radially with respect to the rotation axis X, and a stator core A stator 3 having an insulator 33 for ensuring insulation between 31 and a winding 32, a circuit board 7, and a bottom surface 63a located at the rear B, and opening at the front F to accommodate the circuit board 7. a resin frame 6 having an accommodation space 64, a waterproof resin portion 8 that covers the stator 3 and closes the opening of the accommodation space 64, a bearing 4 that supports the rotating shaft portion 20 so as to be rotatable around the rotation axis X, a metal bearing holder 5 that supports the bearing 4 in a cylindrical shape extending along the rotation axis X;
The frame 6 has a tubular holder protection portion 61 that extends forward F from the bottom surface 63 a and covers at least a portion of the outer peripheral surface of the bearing holder 5 . This holder protection portion 61 separates the stator 3 from the bearing holder 5 .

By the way, the bearing holder 5 is made of metal, and the holder protective portion 61 is generally made of a lightweight non-metallic material such as resin. Therefore, when the waterproof fan 1 is repeatedly subjected to thermal stress, a gap may be formed between the outer peripheral surface of the bearing holder 5 and the inner peripheral surface of the holder protection portion 61 . As a result, water may enter from the interface between the bearing holder 5 and the waterproof resin portion 8 and travel along the outer peripheral surface of the bearing holder 5 to reach the stator 3 located inside the waterproof fan 1 .
However, according to the waterproof fan 1 according to this embodiment, the stator 3 is separated from the bearing holder 5 by the holder protection portion 61 . Therefore, the water that has entered along the outer peripheral surface of the bearing holder 5 does not come into contact with the stator 3 as it is.

In the illustrated example, the front end of the holder protection portion 61 extends to a position that coincides with the front end of the bearing holder 5 . Therefore, water entering between the bearing holder 5 and the holder protection portion 61 is blocked by the holder protection portion 61 and does not reach the stator 3 .

More specifically, the stator 3 of the waterproof fan 1 of this embodiment includes a plurality of stator cores 31 extending radially with respect to the rotation axis, windings 32 wound around the respective stator cores 31, the stator cores 31 and the windings. 32 and an insulator 33 (rear insulator 33B). The inner peripheral surface of insulator 33 is in contact with the outer peripheral surface of holder protection portion 61 . The holder protection portion 61 extends forward (on the other side of the rotation axis) from the contact portion between the holder protection portion 61 and the insulator 33 to block the gap between the bearing holder 5 and the insulator 33 . Therefore, water that has entered along the outer peripheral surface of the bearing holder 5 cannot enter the stator 3 side of the holder protection portion 61 .

In addition, in the example shown in FIG. 2, the shape in which the holder protection portion completely covers the outer peripheral surface of the bearing holder has been described. However, according to the waterproof fan 1 of the present invention, the front end of the holder protection portion 61 may be located behind the front end of the bearing holder 5 as shown in FIG. FIG. 3 shows a waterproof fan 1 according to a modification of the first embodiment of the invention. In this case, it is preferable that the waterproof resin portion 8 exists between the stator 3 and the bearing holder 5 which are separated by the holder protection portion 61 as illustrated.

In the example shown in FIG. 3 , an interface between the holder protection portion 61 and the waterproof resin portion 8 exists on the outer peripheral surface of the bearing holder 5 . Therefore, it is conceivable that the water that has entered along the outer peripheral surface of the bearing holder 5 may further enter the stator 3 from the interface between the holder protection portion 61 and the waterproof resin portion 8 . However, since both the holder protection portion 61 and the waterproof resin portion 8 are made of resin, the interface between the holder protection portion 61 and the waterproof resin portion 8 will not be greatly opened even if the thermal stress is repeatedly applied. Therefore, it is difficult for water to enter the stator 3 from the interface between the holder protection portion 61 and the waterproof resin portion 8 . By forming the holder protective portion 61 and the waterproof resin portion 8 from the same resin, or by forming the holder protective portion 61 and the waterproof resin portion 8 from resins having the same coefficient of linear expansion, water is prevented from entering the stator 3. It becomes easier to prevent intrusion.

Further, according to the waterproof fan 1 , the stator 3 has a plurality of stator cores 31 extending radially with respect to the rotation axis X, and the insulators 33 ensuring insulation between the stator cores 31 and the windings 32 . A through hole 9 penetrating from the front F to the rear B is provided in a part of the circumferential direction between the outer peripheral surface of the holder protection portion 61 and the inner peripheral surface of the insulator 33 . Therefore, when the waterproof resin portion 8 is molded by insert molding, the waterproof resin can smoothly flow from the front F to the rear B or from the rear B to the front F along the through holes 9 . Therefore, the waterproof resin part 8 can be formed by filling the waterproof resin without gaps, and the high waterproofness of the circuit board 7 can be ensured.

FIG. 4 is a perspective view of the frame 6 of the first embodiment of the invention. As shown in FIG. 4, the holder protection portion 61 of the frame 6 extends substantially perpendicularly from the bottom surface 63a in the central portion of the bottom portion 63 with the rotation axis X as the center.

A plurality of protrusions 101 (four in the example shown in the figure) protruding in the radial direction are provided on the outer peripheral surface of the holder protection section 61 . The four protrusions 101 are provided at regular intervals in the circumferential direction. Each projecting portion 101 is provided with a small-diameter projecting portion 101a and a large-diameter projecting portion 101b having different projecting heights. The large-diameter protruding portion 101b is a protruding portion having a higher height than the small-diameter protruding portion 101a. A stepped portion 101c is formed between the small-diameter protruding portion 101a and the large-diameter protruding portion 101b due to the difference in diameter between the two portions. The step portion 101c functions as a board positioning portion that determines the position of the circuit board 7 in the rotation axis X direction. The radial inner end of the circuit board 7 is supported by the stepped portion 101c.

A positioning portion 103 that determines the position of the insulator 33 in the circumferential direction with respect to the holder protection portion 61 is provided on the outer peripheral surface of the holder protection portion 61 in the radial direction. The positioning portion 103 is formed, for example, as a groove along the rotation axis X direction. The position of the insulator 33 with respect to the holder protection portion 61 is determined by fitting a convex portion (not shown) provided on the inner peripheral surface of the insulator 33 in the radial direction to the positioning portion 103 .

FIG. 5 is a top view of the waterproof fan 1 according to the first embodiment of the invention (a view of the waterproof fan 1 viewed from the front side). In FIG. 5, the waterproof resin portion 8 and the winding wire 32 are omitted. As shown in FIG. 5 , a through hole 9 penetrating in the direction along the rotation axis X is provided between the outer peripheral surface of the holder protection portion 61 of the frame 6 and the inner peripheral surface of the insulator 33 . The through hole 9 is provided partially in the circumferential direction. The through hole 9 is provided, for example, between the projecting portions 101 in the circumferential direction of the holder protecting portion 61 . A plurality of through holes 9 are provided in the circumferential direction. As a result, the outer peripheral portion of the holder protective portion 61 has a structure in which a gap communicating from the front side F of the waterproof fan 1 to the bottom surface 63 a of the bottom portion 63 exists along the outer peripheral surface of the holder protective portion 61 .
(Second embodiment)

The waterproof fan of the second embodiment will be described in detail below with reference to FIGS. The description of the content that overlaps with the first embodiment is omitted.

FIG. 6 is a waterproof fan according to a second embodiment of the present invention, which is a cross-sectional view taken along line AA shown in FIG.

As shown in FIG. 6, in the waterproof fan of the second embodiment, the holder protection portion 61 (see FIG. 2) of the waterproof fan of the first embodiment is divided into two parts, a first holder protection portion 61A and a second holder protection portion 61B. It consists of two separate body parts. In other words, the first holder protection part 61A is a part that the frame 6 has, and the second holder protection part 61B is a part that is separate from the frame 6 . The second holder protection portion 61B is a tubular portion provided forward (on the other side of the rotation axis) of the end of the first holder protection portion 61A opposite to the bottom portion 63 . Both the first holder protection portion 61A and the second holder protection portion 61B are inserted through the central portion of the stator 3 .

A portion of the bearing holder 5 having a knurled outer peripheral surface is insert-molded in the first holder protection portion 61A. The first holder protection portion 61A covers part of the outer peripheral surface of the bearing holder 5 .
The second holder protection portion 61B is adhesively fixed to the other portion of the outer peripheral surface of the bearing holder 5 . The second holder protection portion 61B covers the other portion of the outer peripheral surface of the bearing holder 5 .
Thereby, the first holder protection portion 61A and the second holder protection portion 61B separate the stator 3 from the outer peripheral surface of the bearing holder 5 . Therefore, the water that has entered along the outer peripheral surface of the first holder protection portion 61A or the second holder protection portion 61B does not come into contact with the stator 3 as it is.
Also, the space between the first holder protection portion 61A and the second holder protection portion 61B may be sealed with a filler.
This prevents water that has entered along the outer peripheral surface of the first holder protection portion 61A or the second holder protection portion 61B from entering the stator 3 through the gap between the first holder protection portion 61A and the second holder protection portion 61B. Easier to prevent.

In addition, by configuring the holder protection portion from two separate bodies, the first holder protection portion 61A and the second holder protection portion 61B, the front F direction of the holder protection portion (first holder protection portion 61A) of the frame 6 can be length can be shortened. As a result, the roundness of the bearing insertion opening (not shown) of the first holder protection portion 61A for inserting the bearing holder 5 can be ensured during insert molding.

Also, the inner peripheral surface of the insulator 33 is in contact with the outer peripheral surface of the second holder protection portion 61B. The second holder protection portion 61B extends forward (the other side of the rotation axis) from the contact portion between the second holder protection portion 61B and the insulator 33 to block the space between the bearing holder 5 and the insulator 33 . Therefore, water that has entered along the outer peripheral surface of the bearing holder 5 cannot enter the stator 3 side of the second holder protection portion 61B.

In addition, in the example shown in FIG. 6, the shape in which the holder protection portion completely covers the outer peripheral surface of the bearing holder has been described. However, according to the waterproof fan 1 of the present invention, the front end of the second holder protection portion 61B may be located behind the front end of the bearing holder 5 as shown in FIG. FIG. 7 shows a waterproof fan 1 according to a modification of the second embodiment of the invention. In this case, it is preferable that the waterproof resin portion 8 exists between the stator 3 and the bearing holder 5 separated by the second holder protection portion 61B as shown.

Further, according to the waterproof fan 1 , the stator 3 has a plurality of stator cores 31 extending radially with respect to the rotation axis X, and the insulators 33 ensuring insulation between the stator cores 31 and the windings 32 . A through hole 9 penetrating from the front F to the rear B is provided in a portion of the circumferential direction between the outer peripheral surface of the second holder protection portion 61B and the inner peripheral surface of the insulator 33 . Therefore, when the waterproof resin portion 8 is molded by insert molding, the waterproof resin can smoothly flow from the front F to the rear B or from the rear B to the front F along the through holes 9 . Therefore, the waterproof resin part 8 can be formed by filling the waterproof resin without gaps, and the high waterproofness of the circuit board 7 can be ensured.

A positioning portion (not shown) that determines the position of the insulator 33 in the circumferential direction with respect to the second holder protection portion 61B is provided on the radially outer peripheral surface of the second holder protection portion 61B. The positioning portion is formed, for example, as a groove along the rotation axis X direction. The position of the insulator 33 with respect to the holder protection portion 61 is determined by fitting a convex portion (not shown) provided on the inner peripheral surface of the insulator 33 in the radial direction to the positioning portion.

Although the embodiments of the present invention have been described above, it goes without saying that the technical scope of the present invention should not be limitedly interpreted by the description of the embodiments. It should be understood by those skilled in the art that this embodiment is merely an example, and that various modifications of the embodiment are possible within the scope of the invention described in the claims. The technical scope of the present invention should be determined based on the scope of the invention described in the claims and their equivalents.

1 waterproof fan 2 rotor 3 stator 4a first bearing 4b second bearing 5 bearing holder 6 frame 7 circuit board 8 waterproof resin portion 9 through hole 20 rotating shaft portion 21 impeller boss portion 22 rotor cover 31 stator core 32 winding wire 33 insulator 51 first Bearing support portion 52 Second bearing support portion 53 Small diameter portion 61 Holder protection portion 61A First holder protection portion 61B Second holder protection portion 62 Outer cylinder portion 63 Bottom portion 63a Bottom surface 64 Housing space 101 Protruding portion 101c Stepped portion 103 Positioning portion W Rotation Wing X rotation axis

Claims (10)

a rotor comprising a rotary shaft portion rotatable around a rotary axis and rotary blades;
a stator with windings;
a circuit board that energizes the winding;
a resin frame having a bottom surface positioned on one side of the rotation axis and having an accommodation space that opens to the other side of the rotation axis and accommodates the circuit board;
a waterproof resin part that covers the stator and closes the opening of the accommodation space;
a bearing that supports the rotating shaft portion so as to be rotatable around the rotating axis;
a cylindrical bearing holder that supports the bearing and extends along the axis of rotation;
The frame has a cylindrical holder protection portion that extends from the bottom surface to the other side of the rotation axis and covers at least a portion of the outer peripheral surface of the bearing holder, and the holder protection portion protects the stator from the bearing holder. A waterproof fan that is spaced apart. The stator is
a plurality of stator cores extending radially with respect to the rotation axis;
and an insulator that insulates between the stator core and the winding,
The inner peripheral surface of the insulator is in contact with the outer peripheral surface of the holder protection portion,
2. The waterproof fan according to claim 1, wherein the holder protection portion extends to the other side of the rotation axis from a contact portion between the holder protection portion and the insulator to block the gap between the bearing holder and the insulator. . 2. The waterproof fan according to claim 1, wherein the waterproof resin portion exists between the stator and the bearing holder separated by the holder protection portion. The stator is
a plurality of stator cores extending radially with respect to the rotation axis;
and an insulator that ensures insulation between the stator core and the windings,
2. The apparatus according to claim 1, wherein a through hole penetrating from one side of the rotation axis to the other side of the rotation axis is provided in a part of the circumferential direction between the outer peripheral surface of the holder protection portion and the inner peripheral surface of the insulator. waterproof fan. 2. The waterproof fan according to claim 1, wherein a positioning portion for positioning the circuit board is provided on the outer peripheral surface of the holder protection portion. a rotor comprising a rotary shaft portion rotatable around a rotary axis and rotary blades;
a stator with windings;
a circuit board that energizes the winding;
a resin frame having a bottom surface positioned on one side of the rotation axis and having an accommodation space that opens to the other side of the rotation axis and accommodates the circuit board;
a waterproof resin part that covers the stator and closes the opening of the accommodation space;
a bearing that supports the rotating shaft portion so as to be rotatable around the rotating axis;
a cylindrical bearing holder that supports the bearing and extends along the axis of rotation;
the frame has a tubular first holder protection portion that extends from the bottom surface to the other side of the rotation axis and covers a part of the outer peripheral surface of the bearing holder;
a cylindrical second holder protection portion covering the other portion of the outer peripheral surface of the bearing holder is provided on the other side of the rotation axis relative to the first holder protection portion;
The waterproof fan, wherein at least the second holder protection part separates the stator from the bearing holder. The stator is
a plurality of stator cores extending radially with respect to the rotation axis;
and an insulator that insulates between the stator core and the winding,
7. The second holder protection portion according to claim 6, wherein the second holder protection portion extends to the other side of the rotation axis from the contact portion between the second holder protection portion and the insulator to block the gap between the bearing holder and the insulator. Waterproof fan as described. 7. The waterproof fan according to claim 6, wherein the waterproof resin portion exists between the stator and the bearing holder separated by the second holder protection portion. The stator is
a plurality of stator cores extending radially with respect to the rotation axis;
and an insulator that ensures insulation between the stator core and the windings,
7. A through hole penetrating from one side to the other side of the rotation axis is provided in a part of the circumferential direction between the outer peripheral surface of the second holder protection portion and the inner peripheral surface of the insulator. The waterproof fan described in . 7. The waterproof fan according to claim 6, wherein a positioning portion for positioning the circuit board is provided on the outer peripheral surface of the second holder protection portion.

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