JPH0315247A - Blower - Google Patents

Abstract

PURPOSE:To permit the simple and sure cooling of the inside of a blower by a method wherein a cooling air introducing duct for introducing cooling air into a space receiving an armature is provided and the armature is separated from an exciting means by a waterproof structure. CONSTITUTION:Waterproofing casting agent 23 is bonded to a flange 20, from which a cooling air introducing duct 21 is projected, at the abutting part of a casing 5 against a wire holder 22 fitted into a cylinder 10. The air outlet port side of a blower case is communicated with a space 5a in a blower 1, which receives an armature 2, through the cooling air introducing duct 21. The cooling air introducing duct 21 for introducing cooling air into the armature 2 is provided in such a manner and the armature 2 is separated from an exciting means by a waterproof structure whereby the armature is cooled forcibly through the cooling air introducing duct and the power loss thereof may be restrained. On the other hand, the invasion of water drips into the exciting means is prevented by the waterproof structure even when the water drips invade into the blower 1 in accompanied by the forced cooling whereby the generation of faulty insulation and the like may be avoided.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a blower mainly used in a vehicle air conditioner.

(Prior Art) This type of blower is known, for example, one in which a DC brushless motor and a fan are integrally provided on the rotor side. In order to accomplish this, it is well known to send air into the blower from the outlet side of a blower case in which the blower is arranged (see, for example, Japanese Utility Model Publication No. 83697/1983).

(Problem to be Solved by the Invention) However, when the air conditioner takes in air from outside the vehicle, rainwater, etc. becomes mist and is sucked into the blower, and as mentioned above, the air outlet side of the blower case and the blower If it communicates with the inside, water droplets will be sent into the inside of the blower. These water droplets excite the armature, for example, by excitation means (
If it adheres to a circuit (circuit), its insulation properties will be lost over time,
This had the problem of causing poor insulation.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a blower that solves the above-mentioned problems and allows the interior of the blower to be cooled simply and accurately.

(Means for Solving the Problem) In order to achieve the above object, the blower according to the present invention has the following features:
A blower comprising a rotatably provided fan having a field magnet, an armature that generates a rotating magnetic field for the fan, and an excitation means that excites the armature,
A cold air drawing duct is provided for introducing cold air into the space in which the armature is accommodated, and the armature and the excitation means are separated by a waterproof structure.

(Function) Therefore, cooling air is introduced through the cold air intake duct to cool the armature, but the cooling air is blocked by the waterproof structure and does not enter the excitation means, and water particles etc. There is no adhesion to the excitation means of the circuit, and these solve the above problems.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

In Figures 1 to 3, the blower 1 has an armature 2 in the center.
However, the fan 3 is placed above and the printed circuit board 4 is placed below.

The armature 2 is, for example, an iron core 2 formed by laminating silicon steel plates in multiple stages.
The coil 2b is wound in a multi-phase manner such as a Sanwa coil in the slot a, and is fixed to the upper side of the casing 5 by pressing. The armature 2 is configured to generate a rotating magnetic field for the fan 3 by appropriately energizing the coils 2b of each phase from the excitation circuit of the printed circuit board 4 described below.

The printed circuit board 4 is located in a circuit board storage space 5b consisting of a casing 5 and a cover plate l5, and is fixed by screws to the lower side of a flange 20, which will be described later. This allows the cold air intake duct 2l of the flange 20 to pass from the lower side of the printed circuit board 4 toward the armature 2. This printed circuit board 4 has
An excitation circuit (not shown) that excites the armature 2 described above is provided, and a permanent magnet 13 fixed to the shaft 9, which will be described later.
The magnetic pole position of the armature 2 is detected by, for example, a predetermined number of Hall elements 4a arranged on the printed circuit board 4, and based on the detection signal, the coils 2b of each phase of the armature 2 are sequentially and alternately energized with a predetermined phase difference. It has become.

The fan 3 is composed of an impeller 6 made of resin or the like, an annular field magnet (permanent magnet) 7, and a back yoke 8 that suppresses leakage magnetic flux from the field magnet 7. The impeller 6 has a boss portion 6a at its center, and the shaft 9 press-fitted into the boss portion 6a is connected to bearings 11a and llb arranged on a sleeve 10 pressed onto the iron core 2a of the armature 2. It is supported and rotatably secured by washers 12a12b and 12c. A protrusion 6b for sand prevention is provided at the bottom of the impeller 6.
is formed inside the blower I, especially the air gap 3.
0 to prevent sand etc. from entering. For example, the width of the air gap 30 is 1 between the protrusion 6b and the casing 5.
0 for iIn. If the width of the casing 5 is set as narrow as about 7 mm, and the casing 5 is formed into a stepped shape as shown in FIG. 4(a), the passage of sand in the horizontal direction will be suppressed, making it more effective. Alternatively, as shown in FIG. 4) and (C), the end portion may be slightly extended and the tip may be tapered, or furthermore, as shown in FIG. 4(d), the end portion may be tapered. It may be provided (in this case, it becomes the protrusion 5c).

This sand protection prevents sand and the like from entering the inside of the blower 1, thereby preventing the fan 3 from locking up and generating abnormal noise. On the other hand, the field magnet 7 is housed in a groove 6C below the impeller 6 via a back yoke 8, and is fixed with an adhesive or the like. The field magnet 7 is a permanent magnet magnetized with multiple magnetic poles in the circumferential direction, and provides a field to the armature 2. Further, an annular permanent magnet l3 magnetized in the same manner as the field magnet 7 is fixed below the shaft 9, and the above-mentioned Hall element 4a detects the magnetic pole position of this permanent magnet 13. , magnetic pole detection corresponding to the magnetic pole position of the field magnet 7 can be performed.

In the blower 1 configured as described above, the coils 2b of each phase of the armature 2 are alternately energized based on the magnetic pole position of the field magnet 7 of the fan 3, thereby applying a rotating magnetic field to the field magnet 7 of the fan 3. , which causes the fan 3 to rotate.

The blower 1 is used, for example, in a vehicle air conditioner, by being placed in a so-called scroll-type blower case (not shown) and used to suck in and blow out conditioned air.

Next, the internal structure of this blower 1 will be explained in detail.

Similarly, in FIGS. 1 to 3, inside the casing 5 is a substantially annular flange 20 between the armature 2 and the printed circuit board 4, with a cold air drawing duct 2l protruding from a part of the lower part.
are arranged.

This flange 20 has its outer circumferential side abutted against the casing 5 and its inner circumferential side abutted against a wire holder 22 fitted into the sleeve lO, and a waterproof casting agent 23 is bonded to the abutting portions to maintain airtightness. are installed to prevent water from entering between them. Here, as the waterproof casting agent, for example, a resin that hardens upon exposure to air or heat is used. Note that the wire holder 22
A hook 22a is formed in the radial direction, and the hook 22a
The lead wire 2b' of each coil 2b connected from the armature 2 to the printed circuit board 4 is held at point a.

The cold air intake duct 21 is connected such that the end of the opposite flange 20 opens, for example, to the outlet side of the blower case described above. The side communicates with a space 5a in which the armature 2 in the blower 1 is housed.

Therefore, in the casing 5 the armature 2 and the print i
The plate 4 is separated from the plate 4 by a flange 20 with a waterproof structure, and the space 5a housing the armature 2 is communicated with the outlet side of the blower case via a cold air drawing duct 21. Air is blown into the inside of the blower l from the side, so that the inside of the blower l, especially the armature 2, is forcibly cooled. Thereby, the armature 2 is efficiently cooled, power loss is suppressed, and the efficiency of the blower 1 is improved. At the same time, even if, for example, air is taken into the air conditioner from outside the vehicle and water droplets are sent from the blower case to the inside of the blower 1, the air will flow through the airtight flange 20 to the board storage space 5b. flow, and they do not adhere to the excitation circuit of the pudding M plate 4.
The occurrence of insulation defects, etc., which were problems in the past, can be avoided.

Note that the air blown into the blower 1 through the cold air drawing duct 21 is returned into the blower case via the air gap 30.

Here, since the width of the air gap 30 is usually set to about 1 mm, there are cases where the amount of air that escapes through this air gap 30 is insufficient. In order to increase the cooling efficiency, for example, as shown in FIG.
One possible method is to use the proper form of a.

In addition, in this blower 1, a water repellent (for example, fluorine) is applied to either the outer surface of the casing 5 or the field magnet 7.
is applied, and when the blower l stops, the air gap 3
This is to prevent the water droplets accumulated in the fan 3 from freezing and locking the fan 3. For example, as shown in Fig. 6(a), water droplets that accumulate between the casing 5 and the field magnet 7 due to surface tension are caused by the water repellent applied to either one of the former two, as shown in Fig. 6(b). As shown in the figure, the water droplets are biased to one side so that they flow downward. Note that it is effective to apply a water-absorbing agent to the other side of the water-repellent agent, since the water droplets become more uneven and flow downward more easily.

(Effects of the Invention) As described above, according to the present invention, a cold air intake duct for introducing cold air into the armature is provided, and the armature and excitation means are separated with a waterproof structure, so that the armature Power loss is suppressed by forced cooling through the cold air duct, and even if water droplets enter the blower due to forced cooling, the waterproof structure prevents them from entering the excitation means. This solves the conventional problems such as poor insulation and allows the blower to operate stably.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a blower according to an embodiment of the invention, and FIG.
The figure is a perspective view of the same as the above, Fig. 3 is an enlarged sectional view of the vicinity of the flange of the above, Fig. 4 is an enlarged view of the main part between the fan and the casing of the above, and Fig. 5 is a ventilation groove in the field magnet of the above. FIG. 6 is an explanatory diagram showing an example in which water droplets are prevented from accumulating in the air gap. ■... Blower, 2... Armature, 3... Fan, 4
... Printed circuit board, 5... Casing, 6... Impeller, 7... Field magnet, 9... Shaft, 20... Flange, 21... Cold air intake duct. Figure 4 (0) (b) (C) (d) Figure 6 (0) (b) Figure 5 (0》 (b)

Claims (1)

[Scope of Claims] A blower comprising: a rotatably provided fan having a field magnet; an armature that generates a rotating magnetic field for the fan; and excitation means that excites the armature. A blower characterized in that a cold air drawing duct is provided for introducing cold air into a space in which the armature is accommodated, and the armature and excitation means are separated by a waterproof structure.