WO2014147678A1

WO2014147678A1 - Motor fan

Info

Publication number: WO2014147678A1
Application number: PCT/JP2013/006017
Authority: WO
Inventors: 康裕藤井; 敬暁及能; 克弘齊藤; 渡辺　吉典; 鈴木　敦
Original assignee: 三菱重工オートモーティブサーマルシステムズ株式会社
Priority date: 2013-03-21
Filing date: 2013-10-09
Publication date: 2014-09-25
Also published as: US20150369257A1; CN105074227A; JP6126421B2; JP2014181682A; DE112013006329T5; CN105074227B

Abstract

This motor fan (1) is provided with: an impeller (7b) which forms an air current; an electric motor (6) which rotationally drives the impeller (7b); a circular cylindrical casing (16) which covers the outer periphery of the impeller (7b) and through which the air current passes; a shroud (10) which is provided with a base (11) protruding from the periphery of the casing (16); a control unit (40) which controls the rotation of the electric motor (6) and which is installed on the discharge side of the base (11); and a heat sink (50) which radiates heat from heat radiation pins (52), thereby suppressing the heat generation of the control unit (40). In the heat sink (50), the heat radiation pins (52) are exposed to the suction side.

Description

Motor fan

The present invention relates to a motor fan attached to a heat exchanger such as a radiator or a condenser of an automobile, and more particularly to a motor fan that can efficiently cool a controller that controls driving of an electric motor.

In a heat exchanger such as a radiator or a condenser of an automobile, a large amount of air is forcibly passed through a core by a motor fan. The motor fan guides the air flow toward the heat exchanger by covering the space between the periphery of the motor fan and the heat exchanger with a shroud so that the air taken in by the motor fan does not escape sideways.
The motor fan that makes the rotation speed variable includes a controller that controls driving of the electric motor. As this controller, for example, a PWM (Pulse Width Modulation) unit is used. In the PWM unit, when the drive of the electric motor is controlled, a built-in power semiconductor switching element called a power element generates heat. In order to maintain the performance of the PWM unit, it is necessary to cool the power element in order to keep the temperature of the power element below an allowable value. Therefore, the motor fan that makes the rotation speed variable has a configuration for cooling a controller that includes a power element that serves as a heating element.

For example, Patent Document 1 proposes to install a controller inside the shroud and to form a rib that guides air around the controller to the motor fan side. The proposal of patent document 1 is that the excessive temperature rise of a heat generating body can be suppressed by forming a rib and preventing air from stagnating around a controller.
Patent Document 2 presupposes that the PWM unit is disposed facing the fan opening so that the air flow generated by the fan is applied to the PWM unit for forced cooling, and the PWM unit occupies the fan opening. Means capable of changing the area are provided. In Patent Document 2, for example, when the flow rate of the air flow is required to be large so that the PWM unit does not hinder the air flow, the occupied area is reduced.

JP 2006-90243 A JP 2010-151005 A

However, since the proposal of Cited Document 1 is a level that prevents air around the controller from stagnating, it is difficult to obtain a sufficient cooling effect.
In Patent Document 2, since the PWM unit is forcibly cooled, the cooling performance is high. However, even if the occupied area of the PWM unit in the fan opening can be changed to be small, it cannot be denied that the air flow interferes with the PWM unit and hinders the air flow. Therefore, Patent Document 2 inevitably generates noise in addition to a decrease in the air flow rate.
The present invention has been made based on such a technical problem, and an object of the present invention is to provide a motor fan that can efficiently cool a heating element without obstructing an air flow.

The motor fan of the present invention made for such purpose covers an impeller that forms an air flow from the suction side to the discharge side that is the back side of the suction side, an electric motor that rotationally drives the impeller, and an outer periphery of the impeller, A shroud having a cylindrical casing through which an air flow passes, a base projecting around the casing, and a controller including a heating element that is disposed on the discharge side of the base and controls the rotation of the electric motor. The motor fan is characterized in that at least a part of the motor fan is exposed to the suction side, and the temperature rise of the heat generating element is suppressed by a heat radiator that is thermally coupled to the heat generating element.
In the motor fan of the present invention, since the heat radiating body is provided on the base outside the shroud through which the air flow passes, the heat radiating body does not hinder the air flow. Moreover, the motor fan of the present invention is exposed to the suction side where the heat radiating body can receive an air flow, and therefore the heat generating element can be efficiently cooled via the heat radiating body.

The present invention can employ at least the following first to third forms as the form in which the radiator is exposed to the suction side. Both have the same effect that the heat generating element can be efficiently cooled by the air flow formed on the suction side.
In the first form, the heat radiating body is disposed on the discharge side of the base, but the heat radiating body is exposed to the suction side through a through window formed in the base corresponding to the controller.
According to the 1st form, since a heat radiator is exposed to the suction side, a heat generating element can be cooled more efficiently.

In the second embodiment, the heat radiating body is disposed only on the suction side of the base, and is thermally connected to the heat generating element of the controller via the heat transfer body penetrating the base.
According to the second embodiment, since only the region corresponding to the heat transfer body penetrates the base, the rigidity of the shroud can be increased.

In the third embodiment, the heat radiator is integrally formed with the shroud.
According to the 3rd form, since a shroud also exhibits the effect | action which thermally radiates, a heat generating element can be cooled more efficiently.

In the present invention, it is preferable that the heat radiating body is housed in a heat radiating body housing chamber which is provided on the base and retracts toward the discharge side. Since the height at which the heat radiator protrudes can be increased, high heat radiation efficiency can be obtained.

According to the present invention, since the radiator is provided on the outer base of the casing of the shroud through which the airflow passes, the radiator does not hinder the airflow. And since the motor fan of this invention is exposed to the suction side which can receive an air flow at least one part of a heat radiator, a heat generating element can be cooled efficiently via a heat radiator.

The motor fan in 1st Embodiment is shown, (a) is the front view seen from the discharge side, (b) is the front view seen from the suction side. The shroud of the motor fan in 1st Embodiment is shown, (a) is the perspective view seen from the discharge side, (b) is the perspective view seen from the suction side. It is the enlarged view which looked at the control unit vicinity of the motor fan in 1st Embodiment from the suction side. It is an expanded sectional view showing the control unit neighborhood of the motor fan in a 1st embodiment. The motor fan in 2nd Embodiment is shown and it is sectional drawing corresponding to FIG. The motor fan in 3rd Embodiment is shown and it is sectional drawing corresponding to FIG. FIG. 5 is a cross-sectional view corresponding to FIG. 4, showing a modified example of the present invention.

Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.
[First Embodiment]
A motor fan 1 for an automobile according to this embodiment will be described with reference to FIGS.
The motor fan 1 is disposed to face the rear side of the radiator (not shown), and the air flow generated from the front to the rear by rotating is passed through the radiator so that it circulates inside the radiator. Heat is exchanged between the medium and the outside air in the form of airflow. In addition, although the front and back in this embodiment are based on the advancing direction of a motor vehicle, about the motor fan 1, the side facing a radiator is set as the "suction side", and the back side is set as the "discharge side." May be called.

[Configuration: Motor fan 1]
As shown in FIGS. 1 and 2, the motor fan 1 includes the fan 5, the shroud 10 that houses the fan 5 and holds the control unit 40, and the control unit 40 that controls the rotation operation of the fan 5. I have.
The motor fan 1 employs a structure in which the control unit 40 is disposed on the discharge side of the shroud 10, but the heat radiation pins 52 constituting the heat radiator of the control unit 40 are exposed on the suction side of the shroud 10. Therefore, the motor fan 1 can cool the control unit 40 efficiently because the fan 5 rotates and a part of the air flow generated from the suction side toward the discharge side passes through the heat radiation pin 52. Moreover, the motor fan 1 can avoid the control unit 40 from interfering with the air flow by arranging the control unit 40 in the corner 12 of the shroud 10. Hereinafter, each element will be described in order.

As shown in FIG. 1B, the fan 5 includes an electric motor 6 that is fixedly supported on the shroud 10 with bolts, and a fan main body 7 that is connected to a rotating shaft 6 a of the electric motor 6. The fan body 7 includes a bottomed cylindrical boss 7a fixed to the rotating shaft 6a, and an impeller 7b composed of a plurality of blades protruding radially outward from the outer periphery of the boss 7a.

[Configuration: Shroud 10]
The shroud 10 is a member integrally formed by injection molding of a resin, and includes a mortar-shaped base 11 having a rectangular outer shape and a casing 16 provided at a central portion of the base 11.
The base 11 guides the air flow on the suction side to the casing 16. The base 11 includes a fixed frame 13 that fixes the control unit 40 to one of the four corners 12. The fixed frame 13 is provided on the discharge side of the base 11 and has a rectangular outer shape in plan view. The control unit 40 is mounted on the front end of the fixed frame 13 by means such as fastening or bonding. It is fixed to the base 11. Since the through window 14 that connects the tip suction side and the discharge side of the fixed frame 13 is formed, the pin housing chamber 15 penetrates the front and back of the base 11. As will be described in detail later, the heat dissipation pin 52 of the control unit 40 held by the fixed frame 13 penetrates the through window 14 and is exposed to the pin accommodating chamber 15. The interior of the fixed frame 13 forms a pin housing chamber 15 that recedes toward the discharge side from the suction side surface of the base 11.

As shown in FIGS. 1A and 1B, the casing 16 includes an outer ring 17 that protrudes in a cylindrical shape from the discharge-side surface of the base 11, and a discharge grill 18 that covers the tip of the outer ring 17. Yes. The fan 5 is accommodated and held so that the fan main body 7 is arranged toward the suction side in a region surrounded by the outer ring 17 and the discharge grille 18.
The outer ring 17 is made rigid together with the base 11 by fixing the tips of the ribs 19 formed on the discharge side surface of the base 11 to the outer periphery thereof. The rib 19 extends from each of the three corners 12 excluding the place where the fixed frame 13 is provided toward the outer ring 17.
The discharge grill 18 is provided with a plurality of fins 18a radially for the purpose of rectifying the discharged air flow. The discharge grille 18 passes through the front and back except for the portion where the fins 18a are provided, and the air flow generated by the fan 5 passes through the discharge grille 18 and flows to the discharge side. The fixed frame 13 to which the control unit 40 is fixed is located at the corner 12 outside the discharge grill 18, and the air flow passing through the discharge grill 18 does not interfere with the control unit 40.

[Configuration: Control unit 40]
As described above, the control unit 40 is accommodated and held in the fixed frame 13. In the present embodiment, a PWM unit is used as the control unit 40. The PWM unit is an electronic component that controls the rotational speed of the electric motor 6 of the fan 5, and is electrically and mechanically connected to the electric motor 6 through a wiring (not shown).

In the control unit 40, as shown in FIG. 4, a power board 41 and a CPU board 45 are arranged to face each other.
The power board 41 is supplied with a high voltage current from an external high voltage power supply (not shown). The power substrate 41 has a switching element 42 formed of a transistor attached to the surface (front side) facing the CPU substrate 45. A heat transfer plate 44 responsible for heat conduction between the switching element 42 and a heat sink 50 described later is embedded in the power board 41, and the heat transfer plate 44 penetrates the front and back of the power board 41. When the power board 41 and the CPU board 45 are assembled, one surface of the heat transfer plate 44 is in close contact with the switching element 42 and the other surface is in close contact with a heat transfer protrusion 53 of the heat sink 50 described later.
The CPU board 45 is provided with a CPU 37 for controlling the operation of the switching element 42. When a control signal from the CPU 37 is transmitted to the power board 41 and input to the switching element 42, the switching element 42 operates. As a result, a high voltage supplied from the high voltage power supply is applied to the electric motor 6 of the fan 5, and the fan body 7 is rotated at a desired speed. As the switching element 42 operates, the switching element 42 generates heat.
Each element of the control unit 40 described above is covered with a cover 49.

The control unit 40 includes a heat sink 50 that functions as a heat radiator. The heat sink 50 is disposed so as to face the power board 41. When the switching element 42 of the power board 41 generates heat, the heat sink 50 dissipates the heat and prevents the switching element 42 from reaching a temperature exceeding the allowable range.

The heat sink 50 includes a flat sink body 51, a plurality of heat radiation pins 52 provided on one surface side of the sink body 51, and a heat transfer protrusion 53 provided on the other surface side of the sink body 51. Yes. In the heat sink 50, the sink body 51, the heat radiation pin 52, and the heat transfer protrusion 53 are integrally formed by casting an aluminum alloy.

The heat sink 50 is disposed so that the heat transfer protrusion 53 faces the power board 41, and the power board 41, the CPU board 45, and the sink body 51 are fastened by bolts. The control unit 40 is held by the shroud 10 when the sink body 51 is fixed to the fixed frame 13 of the shroud 10. In this state, the tip of the heat transfer protrusion 53 of the heat sink 50 is in close contact with the heat transfer plate 44, and the switching element 42 of the power board 41 and the heat sink 50 are thermally coupled.

In a state where the heat sink 50 is fixed to the shroud 10, the radiating pin 52 passes through the through window 14 formed inside the fixed frame 13 and is accommodated in the pin accommodating chamber 15 as shown in FIG. 3. Therefore, the heat radiation pin 52 that is a part of the heat sink 50 is exposed to the suction side of the shroud 10.

When the fan 5 rotates, the air on the suction side is sucked and discharged as an air flow to the discharge side through the gap of the impeller 7b of the fan body 7. At this time, as shown in FIG. 3, a part of the generated air flow flows from the outer peripheral side to the inner peripheral side along the base 11 of the shroud 10 (reference numeral A in FIG. 3). It can be seen that 15 is on the path of this air flow A. The air flow A has a slower flow velocity than an air flow passing through the inner side of the outer ring 17 of the casing 16, for example. The plurality of heat dissipation pins 52 are arranged in a staggered pattern with respect to the airflow A, and there is a high probability that the airflow A passing through the pin accommodating chamber 15 touches any one of the heat dissipation pins 52. However, the arrangement of the heat radiation pins 52 is a preferable form and is not an element limiting the present invention.

[Action / Effect]
The motor fan 1 having the above configuration has the following operations and effects.
In the motor fan 1, since the control unit 40 including the heat sink 50 is provided at the corner 12 of the shroud 10 (base 11), the control unit 40 does not interfere with the air flow passing through the discharge grill 18. Therefore, in addition to not deteriorating the performance of the motor fan 1, the control unit 40 does not cause noise generation. Further, since the control unit 40 is disposed in the easily accessible corner 12, the motor fan 1 can be easily maintained and inspected.

Moreover, in the motor fan 1, the heat dissipation pins 52 of the heat sink 50 are exposed in the pin housing chamber 15 in the path of the air flow A generated when the motor fan 1 is driven. Therefore, the heat generated in the switching element 42 during driving of the motor fan 1 reaches the heat dissipation pin 52 via the heat transfer plate 44 of the power board 41, the heat transfer protrusion 53 of the heat sink 50, and the sink body 51. Cooling by heat exchange with the stream A is also added, and heat is radiated with high efficiency. The air flow A passes through the heat radiation pin 52 (heat sink 50), but since its flow rate is slow, the generation of noise can be minimized. This also means that the effect of suppressing the pressure loss of the air flow by providing the heat sink 50 can be expected.

Since the motor fan 1 is provided with a pin housing chamber 15 that is recessed from the base 11 and houses the heat dissipation pins 52 therein, the motor fan 1 accommodates the pins in comparison with the case where the heat dissipation pins 52 protrude from the discharge side surface of the base 11. The length of the heat radiation pin 52 can be increased by the depth of the chamber 15. Therefore, the heat radiation efficiency by the heat radiation pin 52 can be increased. If the heat radiation pin 52 is projected from the discharge side surface of the base 11 and the length of the heat radiation pin 52 is approximately the same as that of the present embodiment, the tip of the heat radiation pin 52 projects from the base 11 and the motor fan 1 is fixed. There is a possibility of interfering with the member to be.

[Second Embodiment]
Next, a second embodiment according to the present invention will be described. Since the basic configuration of the second embodiment is the same as that of the first embodiment, the second embodiment will be described below with a focus on differences from the first embodiment.
The motor fan 2 of 2nd Embodiment is provided with the fixed stand 113 corresponding to the fixed frame 13, as shown in FIG. Unlike the fixed frame 13, the fixed base 113 is provided with a solid base 115 at the tip except for the inlay insertion passage 114.
Next, in the motor fan 2, the control unit 40 includes an inlay 48 in which the power board 41 is thermally connected to the switching element 42. The inlay 48 is made of copper or a copper alloy having a high thermal conductivity, and has one end penetrating the power board 41 and closely contacting the switching element 42, and the other end passing through the inlay insertion path 114 of the base 115 of the fixed base 113. It penetrates and is in close contact with the sink body 51 of the heat sink 60. It can be considered that the heat sink 60 is provided with an inlay 48 instead of the heat transfer protrusion 53 of the first embodiment. The heat sink 60 is disposed only on the suction side with the pedestal 115 as a boundary, and the entire heat sink 60 is exposed on the suction side.

In addition to the same effects as the motor fan 1 of the first embodiment, the motor fan 2 has the following effects.
The front end of the fixed frame 13 of the first embodiment is a through window 14, whereas the motor fan 2 is a solid base 115 except for the inlay insertion passage 114. Therefore, the shroud 20 of the second embodiment has higher rigidity than the shroud 10 of the first embodiment.
In the motor fan 2, the heat generated in the switching element 42 during driving reaches the heat dissipation pin 52 via the inlay 48 of the power board 41 and the sink body 51 of the heat sink 60.

[Third Embodiment]
Next, a third embodiment according to the present invention will be described. Since the basic configuration of the third embodiment is the same as that of the first embodiment, the third embodiment will be described below with a focus on differences from the first embodiment.
As shown in FIG. 6, the motor fan 3 of the third embodiment is integrally formed by casting the aluminum alloy including the heat sink 70 in the shroud 30.
Like the heat sink 50, the heat sink 70 includes a sink body 51, a heat dissipation pin 52, and a heat transfer protrusion 53. The sink body 51 is provided so as to close the through window 14 (first embodiment) of the fixed frame 13. It has been.

Since the heat sink 70 is formed integrally with the shroud 30, the motor fan 3 has the following effects in addition to the same effects as the motor fan 1 of the first embodiment.
In addition to the path of the heat transfer plate 44 of the power board 41, the heat transfer protrusion 53 of the heat sink 70, the sink body 51, and the heat dissipation pin 52, the path for radiating the heat generated in the switching element 42 is from the sink body 51 to the shroud 30. Since the route to reach is added, the motor fan 3 can be expected to have a high heat dissipation effect.
Furthermore, since the solid sink body 51 forms a part of the shroud 30 and the shroud 30 does not have a through-hole like the inlay insertion passage 114 of the second embodiment, it is more than the second embodiment. The rigidity of the shroud 30 can be increased.
In addition, the motor fan 3 saves the trouble of assembling the heat sink 70 to the shroud 30.

The embodiments of the present invention have been described above. However, the configurations described in the above embodiments can be selected or modified as appropriate to other configurations without departing from the gist of the present invention.
Although the present embodiment forms the heat dissipation pins 52 having the same height, the present invention can form heat dissipation pins having different heights. In this case, as shown in FIG. 7, the radiating pin 52 close to the outer periphery (upward in the figure) of the shroud 10 is tall, and conversely, the radiating pin 52 close to the inner side (lower in the figure) of the shroud 10 Is preferably lowered. Since the fan 5 is arranged inside the shroud 10, the height is reduced in order to reduce noise caused by the heat radiating pin 52, while the heat radiating pin 52 provided at a position far from the fan 5 emphasizes the effect of heat radiation. And make them taller.

In the present embodiment, the radiating pin 52 is used as a member for radiating heat. However, the present invention is not limited to this, for example, a configuration in which thin plate-like fins are provided at intervals, or on the suction side of the sink main body 51. A dimple-like form having irregularities on the surface can be applied. In the present embodiment, the surfaces of the heat sink 50 that are part of the heat sink 50 and the heat sink pins 52 of the sink body 51 are exposed on the suction side. The protrusion 53 can be exposed to the suction side.

In addition, the pin accommodation chamber 15 has a rectangular shape in plan view, but the present invention is not limited to this, and for example, the width of a portion corresponding to the downstream side of the air flow A in order to allow the air flow A to flow smoothly. Can be expanded.

Moreover, the material which comprises the member of this embodiment is only an illustration, for example, although the heat sink 50 was formed with the aluminum alloy, the heat sink 50 is formed with another metal material, especially copper or copper alloy with high heat conductivity. You can also. Moreover, although the example which formed the heat sink 50 integrally was shown, you may comprise a heat sink combining several members.
In the present embodiment, the switching element 42 is exemplified as the heat generating element, but a resistor is an example of the other heat generating element.

1, 2, 3 Motor fan 5 Fan 6 Motor 6a Rotating shaft 7 Fan body 7a

Boss 7b Impeller

10, 20, 30 Shroud 11 Base 12 Corner 13 Fixed frame 14 Penetration window 15 Pin receiving chamber 16 Casing 17 Outer ring 18 Discharge grille 18a Fin 19 Rib 40 Control unit 41 Power board 42 Switching element (heating element)
44 Heat transfer plate 45 CPU board 48 Inlay 49

Cover

50, 60, 70 Heat sink (heat radiator)
51 Sink body 52 Heat radiation pin 53 Heat transfer protrusion 113 Fixing base 114 Inlay insertion path 115 Base A Air flow

Claims

An impeller that forms a first air flow from a suction side toward a discharge side that is the back side of the suction side;
An electric motor for rotationally driving the impeller;
A cylindrical casing that covers the outer periphery of the impeller and through which the airflow passes;
A base projecting around the casing;
A shroud having,
A motor fan that is disposed on the discharge side of the base and that controls the rotation of the electric motor and that includes a heating element;
At least a part of the motor fan is exposed to the suction side, and a temperature rise of the heat generating element is suppressed by a heat radiating member thermally coupled to the heat generating element.
The radiator is
Exposed to the suction side through a through window formed in the base corresponding to the controller,
The motor fan according to claim 1.
The radiator is
Arranged only on the suction side of the base, and
Thermally connected to the heating element of the controller via a heat transfer body that penetrates the base,
The motor fan according to claim 1.
The radiator is formed integrally with the shroud.
The motor fan according to claim 1.
The shroud is
A radiator housing chamber that is retracted toward the discharge side from the base;
The radiator is housed inside the radiator housing chamber.
The motor fan according to claim 1.
The heating element is a switching element;
The motor fan according to claim 1.
The heat radiator includes a plurality of heat radiation pins.
The motor fan according to claim 1.
The radiator is
A flat sink body,
A plurality of heat dissipation pins provided on the first surface side of the sink body;
A heat transfer protrusion provided on the second surface side of the sink body,
The motor fan according to claim 1.
The radiator is integrally formed by casting an aluminum alloy.
The motor fan according to claim 8.