JP4159650B2 - Axial fan - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an axial fan, and more particularly, to an axial fan that has an excellent heat dissipation effect of a semiconductor element used in a control circuit of a driving motor.
[0002]
[Prior art]
FIG. 5 is a cross-sectional view of an example of an axial fan according to the prior art. In FIG. 5, an impeller 2 is rotatably supported on the inner peripheral surface of the cylindrical wind tunnel portion 1-1 of the venturi case 1 through a small gap. The impeller 2 has a wind tunnel in the venturi case 1. It is rotationally driven by a driving motor 3 held by an electric motor holding cylindrical portion 1-6 connected by a plurality of traversing legs 1-4, and the motor holding cylindrical portion 1-6 A control circuit 5 is housed together with the electric motor 3.
The control circuit 5 uses a semiconductor element 5-2 and is usually mounted on a circuit board 5-1 constituting the control circuit 5 as shown in FIG. 5, but with the need for high performance and downsizing, There is a real demand for improvement in the heat dissipation effect of the semiconductor element 5-2.
[0003]
In FIG. 5, since the control circuit 5 is housed together with the electric motor 3 in a small space in the electric motor holding cylindrical portion 1-6, there is little escape space for heat generation by the semiconductor element 5-2 and the like, and the convection of the internal air is easy. Countermeasures such as downsizing and radiating fins are countermeasures, but this is an issue for improvement especially as miniaturization progresses.
[0004]
[Problems to be solved by the invention]
In the conventional configuration as described above, in order to satisfy the contradictory requirements of high performance and downsizing, it is an object to realize a means with a simple configuration and excellent heat dissipation effect.
[0005]
[Means for Solving the Problems]
An axial fan according to the present invention includes a venturi case having a cylindrical wind tunnel portion formed of a metal member, a semiconductor element for configuring a control circuit and controlling a winding current of the motor, and the cylindrical wind tunnel portion. Fixed to the inner surface of the disc-shaped bottom portion of the motor holding cylindrical portion connected to each other by a plurality of legs, and the disc-shaped bottom portion is configured such that a window and a groove serve as an insertion passage for the leader line of the control circuit. A U-shaped groove is formed on one side of the window, and the U-shaped groove is configured to be a fitting portion of a screw member for fastening and holding the semiconductor element disposed on the inner surface of the disk-like bottom portion. Alternatively, the disk-shaped bottom portion of the electric motor holding cylindrical portion connected to and integrated with the cylindrical wind tunnel portion by a plurality of legs includes a concave portion for mounting the semiconductor element on an outer surface thereof, and the concave portion and the legs. A window communicating with the formed groove, and the semiconductor element While being accommodated secured in the recess of the disk-like bottom portion, the window and the grooves are constructed as a through location of the lead line of the control circuit.
[0006]
In the configuration as described above, it is possible to realize a means having an excellent heat dissipation effect with a simple configuration without obstructing the contradictory requirements of high performance and downsizing.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view of a first example of an axial fan according to the present invention, FIG. 2 is an enlarged sectional view of a main part of the example, FIG. 3 is a front view of a second example of the present invention, and FIG. FIG.
[0008]
A first example shown in FIG. 1 and FIG. 2 is a semiconductor element 5-2 that generates heat on the inner surface of a disk-like bottom portion 1-7 of a motor holding cylindrical portion 1-6 and that has been mounted on a conventional circuit board 5-1. The semiconductor element 5-2 that generates heat is brought into contact with and fixed to the electric motor holding cylindrical portion 1-6 integrated with the venturi case 1 formed of a metal member, thereby enabling effective heat dissipation. Is.
[0009]
In this example, the shallow concave portion is formed in the disk-like bottom portion 1-7, on the assumption that the screw member 8 is used as a fastening fastening means for the semiconductor element 5-2. Is considered so as not to come into contact with the name plate 7 attached as an outer covering member.
[0010]
In the second example shown in FIG. 3 and FIG. 4, the semiconductor element 5-2 is abutted and fixed to the outer surface of the disk-like bottom portion 1-7 for the purpose of improving workability in the mounting operation. It is the structure to do.
In this example, a concave portion 1-10 that can accommodate the semiconductor element 5-2 outside the disc-shaped bottom portion 1-7, and a window 1-8 that is connected to the concave portion 1-10 and passes through the lead wire 6; And connecting the semiconductor element 5-2 to the outside of the concave groove 1-10 with a screw member 8 and connecting the terminal of the semiconductor element 5-2 to the circuit board through the window 1-8. Is supposed to be connected. With this configuration, the semiconductor element 5-2 that generates a large amount of heat can be retrofitted onto the outer surface of the disk-shaped bottom 1-7.
[0011]
In any of the above examples, the window 1-8 is formed so as to communicate with the inside of the disk-shaped bottom portion 1-7, and is drawn out to the foot connecting the wind tunnel portion 1-1 of the venturi case 1 and the motor holding cylindrical portion 1-6. Although the line insertion groove 1-5 is provided, the insertion line of the lead line itself has a conventionally well-known configuration. Then, as described above, the name plate 7 is attached so as to cover the semiconductor after the semiconductor element 5-2 is mounted and fixed. This is also a well-known configuration as a consideration in terms of appearance design.
[0012]
【The invention's effect】
The axial fan according to the present invention uses a part of a venturi case made of a metal member as a heat radiating member for a semiconductor, so that it is not necessary to use a special member for radiating heat, and a heat generating semiconductor can be obtained by simple means. The effect which can implement | achieve the thermal radiation effect of an element is brought about.
[Brief description of the drawings]
FIG. 1 is a front view of a first example of an axial fan according to the present invention.
FIG. 2 is an enlarged cross-sectional view of a main part of the example of FIG.
FIG. 3 is a front view of a second example of the axial fan according to the present invention.
4 is an enlarged cross-sectional view of a main part of the example of FIG.
FIG. 5 is a cross-sectional view of an example of an axial fan according to the prior art.
[Explanation of symbols]
1 Venturi case 1-1 Cylindrical wind tunnel 1-4 Foot 1-5 Groove 1-6 formed in foot 1-6 Motor holding cylinder 1-7 Disc-shaped bottom 1-8 Window 1 through which the leader line of the bottom is inserted 9 U-groove 1-10 for screw fitting to be formed on one side of window 2 Recess 2 for mounting semiconductor element Impeller 3 Electric motor 3-1 Stator 3-2 Rotor 3-3 Rotor shaft 3-4 Rotor hub 4 Bearing 5 Control circuit 5-1 Circuit board 5-2 Semiconductor element 6 Leader 7 Name plate 8 Screw member

Claims (1)

A venturi case having a cylindrical wind tunnel portion formed of a metal member, an impeller rotatably supported by a plurality of blades opposed to the inner peripheral surface of the wind tunnel portion via a small gap, and driving the impeller Therefore, in an axial fan including an electric motor and a control circuit for controlling the electric motor, a plurality of semiconductor elements constituting the control circuit and controlling a winding current of the electric motor are provided in the cylindrical wind tunnel portion. Fixedly attached to the disk-like bottom of the motor holding cylindrical part connected and integrated with the legs of
The disk-shaped bottom portion of the electric motor holding cylindrical portion that is connected to and integrated with the cylindrical wind tunnel portion by a plurality of legs includes a window that communicates with a groove formed in the foot on an outer surface thereof, and the semiconductor element is the circle. The window and the groove are fixed to the inner surface of the plate-like bottom portion, and are configured so as to serve as an insertion passage for the leader line of the control circuit,
A shaft characterized in that a U-shaped groove is formed on one side of the window, and the U-shaped groove is a fitting portion of a screw member for fastening and holding a semiconductor element disposed on the inner surface of the disk-shaped bottom portion. Flow fan.

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