Waterproof fan

Abstract

To provide a waterproof fan with high bonding strength between a waterproof cover and an epoxy resin.SOLUTION: A waterproof fan comprises: a rotary vane W rotatable around an axis of a rotary shaft 20; a rotor 3 having a permanent magnet 33; a plurality of stator cores located on an inner diameter side than the rotary vane W and extending in the radial direction with respect to the axis of the rotary shaft 20; a stator 4 having a winding 42 wound around each of the stator cores; a circuit board 5 electrically connected to the winding 42; a waterproof cover 6 made of a first resin covering the circuit board 5; and a mold part 7 made of a second resin covering at least the stator 4. The waterproof cover 6 is provided with a partition part 64 separating the winding 42 and the circuit board 5, and a protruded part 65 protruded from the partition part 64 toward a space between the windings 42. A gap between the winding 42, the partition part 64 and the protruded part 65 is embedded with a second resin that constitutes the mold part 7.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a waterproof fan. [Background technology]

[0002] Patent Document 1 discloses a waterproof fan. This waterproof fan aims to waterproof the windings of the motor that drives the fan by molding the windings with resin. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-117635 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, in the waterproof fan described in Patent Document 1, the space around the substrate and the space around the windings are filled with waterproof resin (epoxy resin) to waterproof the substrate and the windings. However, because such a structure requires a large amount of epoxy resin to be filled, consideration is being given to partitioning the space that houses the board from the space in which the windings are arranged with a waterproof cover, waterproofing the space that houses the board with the waterproof cover, and filling only the area around the windings with epoxy resin to waterproof the windings.

[0005] However, it has been discovered that in a structure using a waterproof cover, when the ambient temperature becomes high or low, the difference in linear expansion coefficient between the metal or resin waterproof cover and the epoxy resin creates thermal stress between them, which can cause the waterproof cover to peel off from the epoxy resin.

[0006] SUMMARY OF THE PRESENT DISCLOSURE The present invention provides a waterproof fan having a strong bond between the waterproof cover and the waterproof resin. [Means for solving the problem]

[0007] A waterproof fan according to one aspect of the present invention includes: A rotor having a rotor blade rotatable about a rotation axis and a permanent magnet; a stator including a plurality of stator cores located radially inward of the rotor blades and extending radially with respect to the rotation axis, and a winding wound around each of the stator cores; a circuit board electrically connected to the winding; a first resin waterproof cover for covering the circuit board; a second resin molded portion that covers at least the stator, The waterproof cover is a partition portion separating the winding and the circuit board; a protrusion is provided protruding from the partition toward a space between the windings, The gaps between the winding, the partition portion, and the protrusion are filled with the second resin. Effect of the Invention

[0008] According to the present invention, it is possible to provide a waterproof fan having a strong bond between the waterproof cover and the waterproof resin. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a front view of the waterproof fan according to the embodiment of the present invention. [Diagram 2] FIG. [Diagram 3] FIG. [Figure 4] 3 is a cross-sectional view of the waterproof fan taken at a position different from that in FIG. 2. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. For the sake of convenience, the description of the components having the same reference numbers as those already described in the description of the embodiment will be omitted. Also, for the sake of convenience, the dimensions of each component shown in the drawings may differ from the actual dimensions of each component.

[0011] Fig. 1 is a front view of a waterproof fan 1 according to an embodiment of the present invention. Fig. 3 is a front perspective view of a waterproof cover 6 (first cover 61) provided on the waterproof fan 1. In the following description, for convenience, in the drawings, the letter F indicates the front of the waterproof fan 1 and the letter B indicates the rear of the waterproof fan 1.

[0012] 1, the waterproof fan 1 includes multiple (seven in this example) rotor blades W that can rotate around a rotary shaft 20, and a cylindrical casing C that surrounds the radial outer periphery of the rotor blades W. The waterproof fan 1 generates an airflow that flows from one side of the rotation axis A of the rotary shaft 20 to the other side by the rotation of the rotor blades W. In the following description, for convenience, one side of the rotation axis A may be referred to as the front F and the other side as the rear B.

[0013] The multiple rotors W are attached radially around the hub portion 21. The hub portion 21 is formed in a roughly cup shape, and is provided so as to surround the periphery of the rotating shaft 20. In the waterproof fan 1 shown in Figure 1, the inside of the stator 4 is depicted by dashed lines.

[0014] The rotor W is attached to the hub portion 21. The rotor W generates an airflow between the rotor W and the casing C as the rotor W rotates. The rotor W is formed in a shape and structure that generates an airflow from one side to the other side of the rotation axis A. The casing C that surrounds the rotor W has a rectangular frame portion 22 and a circular air duct portion 23 that is defined in the center of the frame portion 22 and guides the airflow.

[0015] Fig. 2 is a cross-sectional view taken along line II-II in Fig. 1. Fig. 4 is a cross-sectional view taken along line II-IV in Fig. 1. 2 and 4, the waterproof fan 1 includes a motor 2 for driving and rotating the rotor W. The motor 2 is provided inside a hub portion 21 to which the rotor W is attached. The motor 2 is, for example, an outer rotor type brushless motor. The motor 2 has a stator 4 and a rotor 3 arranged on the outer periphery of the stator 4.

[0016] The rotor 3 has a generally cup-shaped rotor cover 31, a rotating shaft 20 press-fitted into the center of the rotor cover 31 by a bush 32, and a permanent magnet 33 fixed to the rotor cover 31. The rotor cover 31 is fitted into the hub portion 21. The hub portion 21 into which the rotor cover 31 is fitted fixes the rotating shaft 20 via the bush 32.

[0017] The rotor cover 31 is made of a magnetic material such as a carbon steel casting (SC material). Permanent magnets 33 are fixed to the inner peripheral surface of the rotor cover 31 along the axial direction so as to be aligned in the circumferential direction. The rotor cover 31 closes the magnetic field lines to enhance the electromagnetic induction effect.

[0018] The rotating shaft 20 is rotatably supported by a bearing 24 fixed to a stator frame 25, which will be described later. The bearing 24 is fixed to the inner circumferential surface of a cylindrical bearing holder 26 formed in the center of the stator frame 25.

[0019] The stator 4 includes a plurality of stator cores 41 arranged radially inward of the rotor W, windings 42 wound around each of the stator cores 41, and a stator frame 25.

[0020] The stator frame 25 is generally cup-shaped. The stator frame 25 and the hub portion 21 to which the rotor blades W are attached are provided along the direction of the rotation axis A with the insides of the cup shapes facing each other.

[0021] Each stator core 41 extends in a radial direction relative to the rotation axis A. Each stator core 41 is formed by laminating a plurality of thin metal plates in the thickness direction. The material of the stator core 41 is, for example, a silicon steel plate.

[0022] Each stator core 41 is provided on the outer periphery of the bearing retaining portion 26 via an insulator 43. The insulator 43 is composed of an upper insulator 43A provided on the upper surface of the stator core 41 and a lower insulator 43B provided on the lower surface of the stator core 41. The upper insulator 43A is provided with an upper inner protrusion and an upper outer protrusion extending in the direction of the rotation axis A. An upper slot 44A is formed between the upper inner protrusion and the upper outer protrusion. The lower insulator 43B is also provided with a lower inner protrusion and a lower outer protrusion extending in the direction of the rotation axis A. A lower slot 44B is formed between the lower inner protrusion and the lower outer protrusion.

[0023] The winding 42 is wound around the stator core 41. The winding 42 is housed between the upper slot 44A and the lower slot 44B. The upper insulator 43A is located between the winding 42 and the upper surface of the stator core 41, and the lower insulator 43B is located between the winding 42 and the lower surface of the stator core 41, so that the winding 42 is not electrically connected to the stator core 41. In addition, as viewed from the direction of the rotation axis A, the upper insulator 43A is larger in shape than the stator core 41, and the lower insulator 43B is larger in shape than the stator core 41. Therefore, the winding 42 located between the upper insulator 43A and the lower insulator 43B is also not electrically connected to the stator core 41.

[0024] The waterproof fan 1 further includes a circuit board 5 supported by the stator frame 25 and a waterproof cover 6 that covers the circuit board 5.

[0025] The circuit board 5 is disposed behind the stator 4. A wiring pattern for controlling the motor 2 is formed on the circuit board 5. The circuit board 5 is electrically connected to the windings 42 wound around the stator core 41. Connection terminals 51 connected to the wiring pattern are soldered to the circuit board 5. The circuit board 5 is electrically connected to the windings 42 by connecting the windings 42 to the connection terminals 51. Although not shown, a lead wire for supplying power to the waterproof fan 1 is connected to the circuit board 5.

[0026] The waterproof cover 6 has a first cover 61 that covers the circuit board 5 from the front side, and a second cover 62 that covers the circuit board 5 from the rear side. The circuit board 5 is accommodated in an accommodation space 63 formed by the first cover 61 and the second cover 62. The waterproof cover 6 (the first cover 61 and the second cover 62) is made of an electrically insulating synthetic resin.

[0027] 2 and 3, the first cover 61 is a cup-shaped member that opens to the rear. The first cover 61 has a partition 64 that separates the windings 42 wound around the stator core 41 from the circuit board 5, and a plurality of (four in this example) protruding portions 65 that protrude forward from the partition 64.

[0028] The partition portion 64 is a plate-like portion extending along a plane intersecting the rotation axis A. An insertion hole 66 is provided in the center of the partition portion 64, through which the rotating shaft 20, the bearing 24, the bearing holder 26, etc. are inserted. In addition, a communication hole 67 is provided on the periphery of the partition portion 64, through which the communication terminal 51 soldered to the circuit board 5 is inserted.

[0029] The protruding portion 65 is a cylindrical portion extending along the rotation axis A. When viewed from the direction of the rotation axis A, the protruding portion 65 protrudes toward the spaces between the windings 42 and is provided so as to fill the spaces. The inside of the protruding portion 65 is formed to form a cavity 65h. In the illustrated example, the cross section of the protruding portion 65 cut across the protruding direction has an isosceles trapezoidal shape.

[0030] The first cover 61 is attached so that the communication terminals 51 of the circuit board 5 are inserted into the communication holes 67 of the partition portion 64 and each of the protrusions 65 is positioned within the space between the windings 42 wound around each stator core 41.

[0031] 2 and 4, the second cover 62 has a shape corresponding to the shape of the stator frame 25, and is provided inside the cup-shaped stator frame 25. A recess 69 is formed on the edge of the second cover 62, and the recess 69 of the second cover 62 fits into a protrusion 68 formed on the edge of the first cover 61, thereby forming the waterproof cover 6.

[0032] As shown in FIG. 2, the waterproof cover 6 is arranged such that an end 65e of the protrusion 65 of the first cover 61 on the side farther from the circuit board 5 (front side) is positioned closer to the circuit board 5 (rear side) in the direction of the rotation axis A than an end 42e of the winding 42 wound around the stator core 41 on the side farther from the circuit board 5.

[0033] As shown in Figs. 2 and 4, the waterproof fan 1 also includes a molded portion 7 that covers the stator 4. The molded portion 7 is made of an electrically insulating synthetic resin. For example, the molded portion 7 is made of a thermosetting epoxy resin. The molded portion 7 is provided so as to fill the gap between the winding 42 wound around the stator core 41 and the partition portion 64 and the protruding portion 65 of the first cover 61 of the waterproof cover 6, so as to cover at least the stator 4. The resin that constitutes the molded portion 7 may be a different resin from the resin that constitutes the waterproof cover 6 (the first cover 61 and the second cover 62), or may be the same resin.

[0034] The resin constituting the molded portion 7 is provided so as to cover the periphery of the stator 4 while being arranged so as not to enter the housing space 63 in which the circuit board 5 is housed. In addition, the resin constituting the molded portion 7 passes from the outside of the waterproof cover 6 through the communication hole 67 of the first cover 61, and enters the communication hole 67 so as to surround the communication terminal 51 and block the communication hole 67, while also running along the communication terminal 51 and protruding slightly from the communication hole 67 into the storage space 63.

[0035] As described above, in the waterproof fan 1 according to this embodiment, the waterproof cover 6 has a partition 64 that separates the windings 42 wound around the stator core 41 from the circuit board 5, and a protrusion 65 that protrudes from the partition 64 into the space between the windings 42. The gaps between the windings 42, the partition 64, and the protrusion 65 are filled with synthetic resin (molded portion 7), so that the stator 4 of the waterproof fan 1 is covered with the molded portion. As a result, the contact area between the waterproof cover 6 and the molded portion 7 can be increased by the protrusion 65, thereby increasing the bonding strength between the waterproof cover 6 and the molded portion 7. Therefore, even if the waterproof cover 6 and the molded portion 7 have different linear expansion coefficients and thermal stress occurs between them, it is possible to prevent the waterproof cover 6 from peeling off the molded portion 7.

[0036] As a method for covering the stator part of the waterproof fan, for example, a method of filling the space between the waterproof cover and the windings of the stator part with silicone resin is also used. However, in this method, since the space between the waterproof cover and the windings is large, it takes time to fill the silicone resin, and production efficiency is poor. In contrast, according to the waterproof fan 1 of this embodiment, the protrusion 65 of the waterproof cover 6 protrudes into the space between the windings 42 and already fills the space between the windings 42, so the amount of silicone resin to be filled can be significantly reduced. This improves production efficiency.

[0037] Moreover, according to the waterproof fan 1, the protruding portion 65 is formed so that the inside is hollow 65a. Therefore, since the protruding portion 65 has a structure that is easily deformed, even if the protruding portion 65 is pushed by the molded portion 7 as the molded portion 7 expands, the deformation of the protruding portion 65 can prevent excessive force from acting on the protruding portion 65 and the molded portion 7. Furthermore, since the amount of resin filled in the molded portion 7 is reduced by the protruding portion 65, the force generated when the molded portion 7 expands can be reduced, and excessive force is less likely to act on the winding 42.

[0038] Moreover, according to the waterproof fan 1, the partition 64 is a plate-like portion extending along a plane intersecting the rotation axis A, and the protruding portion 65 is formed to be a cylindrical portion extending along the rotation axis A. Therefore, when the molded portion 7 expands and contracts in the direction of the rotation axis A, the partition 64 is likely to maintain its connection with the molded portion 7, and when the molded portion 7 expands and contracts in a direction perpendicular to the rotation axis A, the protruding portion 65 is likely to maintain its connection with the molded portion 7. In other words, even if the molded portion 7 expands and contracts in any direction, the partition 64 and the protruding portion 65 extend in different directions, so that the joined state between the molded portion 7 and the waterproof cover 6 is likely to be maintained.

[0039] Moreover, according to the waterproof fan 1, the waterproof cover 6 includes a first cover 61 having a partition portion 64 and a protrusion portion 65, and a second cover which, together with the first cover 61, forms an accommodation space 63 for accommodating the circuit board 5. The molded portion 7 is configured not to enter the accommodation space 63 that accommodates the circuit board 5. This makes it possible to reduce the amount of synthetic resin used to form the molded portion 7, and to reduce the weight of the waterproof fan 1.

[0040] Furthermore, according to the waterproof fan 1, the end 65e of the protruding portion 65 of the first cover 61 on the side farther from the circuit board 5 is provided to be located closer to the circuit board 5 than the end 42e of the winding 42 wound around the stator core 41 on the side farther from the circuit board 5 in the direction of the rotation axis A. Therefore, the protruding portion 65 arranged in the space between the windings 42 is located inside the windings 42, so that when the surface of the stator 4 is covered with the molded portion 7, the protruding portion 65 can be covered so as not to protrude from the molded portion 7. This ensures high waterproofing without creating a gap between the protruding portion 65 and the molded portion 7.

[0041] Furthermore, according to the waterproof fan 1, the first cover 61 is provided with a communication hole 67 through which a communication terminal 51 is inserted to electrically connect the circuit board 5 and the winding 42. The resin constituting the molded portion 7 enters the communication hole 67 from the outside of the waterproof cover 6 through the communication hole 67 of the first cover 61, blocking the communication hole 67, and is provided in a state in which it slightly enters the accommodation space 63. This makes it possible to achieve electrical connection between the circuit board 5 and the winding 42 while waterproofing the accommodation space 63.

[0042] Although the embodiment of the present invention has been described above, it goes without saying that the technical scope of the present invention should not be interpreted as being limited by the description of the embodiment. The embodiment is merely an example, and it is understood by those skilled in the art 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 its equivalents. [Explanation of symbols]

[0043] 1 waterproof fan 2 Motors 3 Rotor 4 Stator 5 Circuit Board 6 Waterproof cover 7 Molded part 20 Rotational Axis 25 Stator frame 31 Rotor cover 33 Permanent Magnets 41 Stator core 42 Windings 42e end 51 Contact terminal 61 First Cover 62 Second cover 63 Containment Space 64 Partition 65 Protrusion 65e end 65h hollow 67 Connection hole W Rotor

Claims

1. A rotor having a rotor blade rotatable about a rotation axis and a permanent magnet; a stator including a plurality of stator cores located radially inward of the rotor blades and extending radially with respect to the rotation axis, and a winding wound around each of the stator cores; a circuit board electrically connected to the winding; a first resin waterproof cover for covering the circuit board; a second resin molded portion that covers at least the stator, The waterproof cover is a partition portion separating the winding and the circuit board; a protrusion is provided protruding from the partition toward a space between the windings, a gap between the winding, the partition portion, and the protruding portion is filled with the second resin, A waterproof fan, wherein at least a portion of the protrusion extends into a space between the windings.

2. The waterproof fan according to claim 1 , wherein the inside of the protrusion is hollow.

3. the partition portion is a plate-shaped portion extending along a plane intersecting the rotation axis, The waterproof fan according to claim 1 , wherein the protrusion is a cylindrical portion extending along the rotation axis.

4. The waterproof cover is a first cover including the partition portion and the protrusion portion; a second cover which, together with the first cover, defines an accommodation space for accommodating the circuit board; The waterproof fan according to claim 1 , wherein the second resin does not enter the accommodation space.

5. The waterproof fan according to claim 1 , wherein, in the direction of the axis of rotation, the end of the protrusion farther from the circuit board is located closer to the circuit board than the end of the winding farther from the circuit board.

6. the first cover is provided with a communication hole through which a communication terminal for electrically connecting the circuit board and the winding is inserted, The waterproof fan according to claim 4 , wherein the second resin flows into the accommodation space from outside the accommodation space through the communication hole.

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