JP2006077646A - Cooling device provided with electric motor driving cooling fan - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce aerodynamic noise by a heat sink of a control device controlling an electric motor driving a cooling fan and to miniaturize the heat sink further. <P>SOLUTION: A cooling device 1 is provided with a radiator 2 including an outlet tank 23 in which cooling water radiating heat in a radiator core 2 flows, a brushless motor 5 driving the cooling fan 3, the control device 6 controlling the brushless motor 5. The control device 6 is divided into a first control part 61 including a first circuit element group 63, and a second control part 62 including second circuit element group which generates larger quantity of heat than the first circuit element group 63. The second control part 62 attached to the outlet tank 23 includes the heat sink including heat radiation fin touching cooling water in the outlet tank 23. The whole the heat sink is arranged at a position not overlapping with the cooling fan 3 in a view from a direction of rotation center line L of the cooling fan 3. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a cooling device including an electric motor that drives a cooling fan that generates cooling air to be sent to a heat dissipation device through which a fluid to be cooled flows, and more particularly, to a heat sink provided in a control device that controls the operation of the electric motor. .

  As an electric motor that drives a cooling fan that generates cooling air for cooling a radiator of an internal combustion engine and a condenser of an air conditioner, for example, a brushless motor is employed. A brushless motor has a larger output and higher efficiency than a brushed motor, but also generates a large amount of heat from a circuit element group constituting a control circuit of the control device. For this reason, the control circuit of the brushless motor is provided with an air-cooled heat sink that is cooled by being exposed to air as in the technique disclosed in Patent Document 1, and the control device is cooled by the heat sink.

  In order to increase the amount of heat released by the air-cooled sheet sink, the heat radiating fins of the heat sink may be disposed in the downstream or suction flow of the cooling fan. However, the heat dissipating fins of the heat sink arranged in the wake or suction flow of the cooling fan generate a large amount of vortices, and the generated vortices inhibit the smooth flow of cooling air, resulting in pressure fluctuations. It causes aerodynamic noise and causes a reduction in air volume.

Also known is a water-cooled heat sink that radiates heat to water in order to increase the amount of heat released from the heat sink. For example, the water-cooled heat sink disclosed in Patent Document 2 is provided so as to penetrate the outer surface of a tank of an engine radiator and is exposed to the cooling water in the tank.
Japanese Patent Laid-Open No. 11-332203 JP-A-11-192901

  If the control device that controls the electric motor that drives the cooling fan generates a large amount of heat, the air-cooled heat sink has a larger radiating fin, even if the heat sink is exposed to cooling air to ensure the required heat dissipation performance. There is a drawback that aerodynamic noise increases. On the other hand, by using a liquid-cooled heat sink, it is possible to reduce the size as compared with the air-cooled type, but further downsizing is desirable.

  This invention is made in view of such a situation, and while the invention of Claims 1-3 aims at reduction of the aerodynamic noise by the heat sink of the control apparatus which controls the electric motor which drives a cooling fan, The object is to further reduce the size of the heat sink.

  The invention according to claim 1 is a heat radiating device having a heat radiating core through which a fluid to be cooled flows, and an outlet tank into which the fluid to be cooled after radiating the cooling air in the heat radiating core flows in a liquid state, and the cooling A cooling device comprising: an electric motor that drives a cooling fan that generates wind; and a control device that includes a heat sink that dissipates heat generated by a circuit element group that constitutes a control circuit that controls the electric motor. The cooling apparatus has a heat radiating portion that is disposed in a portion that does not overlap with the cooling fan when viewed from the rotation center line direction of the cooling fan, and the heat sink has a heat radiating portion that contacts the liquid to be cooled in the outlet tank. It is.

  According to this, since the entire heat sink is not exposed to the cooling air in the rotation center line direction within the projection area of the cooling fan in the rotation center line direction, the generation of vortex by the heat sink is greatly reduced. Furthermore, the heat generated by the circuit element group is radiated to the cooled fluid in the low-temperature liquid state after being radiated by the heat radiating core through the heat sink. As a result, the heat dissipation amount is increased and the heat dissipation performance of the heat sink is improved.

  According to a second aspect of the present invention, in the cooling device according to the first aspect, the circuit element group includes a first circuit element group and a second circuit element or a second circuit that generates a larger amount of heat than the first circuit element group. The control device is divided into a first control unit having the first circuit element group and a second control unit having the second circuit element or the second circuit element group, and The second control unit has the heat sink.

  According to this, the second circuit element group, which is a part of the circuit element group that is a part of the circuit element group that generates a large amount of heat and has a high cooling requirement, is separated from the first circuit element group, and the second circuit element group Since the generated heat is radiated to the cooled fluid in the outlet tank through the heat sink, the first and second circuit element groups are compared with the case where one heat sink is used for the first and second circuit element groups. In addition to ensuring the required cooling performance for each of these, the heat sink is reduced in size.

  According to a third aspect of the present invention, in the cooling device according to the first or second aspect, the heat radiating core includes a heat transfer tube connected to the outlet tank and through which the fluid to be cooled flows, and the heat radiating portion. Is composed of a heat radiating protrusion protruding into the outlet tank, and the heat radiating protrusion is in a position where the liquid to be cooled from the heat transfer tube collides with the extension of the heat transfer tube. is there.

  According to this, since the low-temperature liquid cooled fluid flowing into the outlet tank from the heat transfer tube collides with the heat radiating protrusion due to inertia when flowing into the outlet tank from the heat transfer tube, the temperature boundary layer is extremely low. It becomes thin, and the amount of heat radiation at the heat radiating protrusion is increased by the contact with the low-temperature fluid to be cooled, so that the heat radiation performance of the heat sink is improved.

  According to invention of Claim 1, the following effect is show | played. That is, since the generation of vortices by the heat sink is greatly reduced, aerodynamic noise due to the generation of the vortices is greatly reduced and the air volume of the cooling fan is increased. In addition, the heat dissipation performance of the heat sink is improved by dissipating the heat of the circuit element group to the liquid fluid to be cooled after being radiated by the heat radiating core, so that the heat sink can be downsized.

  According to invention of Claim 2, in addition to the effect of the invention of the cited claim, there exists the following effect. That is, since the heat of the second circuit element group having a high cooling requirement among the circuit element groups is radiated to the cooled fluid in the outlet tank through the heat sink, the required cooling performance of the circuit element group is ensured, The heat sink can be downsized.

  According to invention of Claim 3, in addition to the effect of the invention of the cited claim, there exist the following effects. That is, since the heat dissipation performance of the heat sink is improved by the collision of the fluid to be cooled from the heat transfer tube with the heat dissipation protrusion, the heat sink can be downsized.

Embodiments of the present invention will be described below with reference to FIGS.
Referring to FIG. 1, a cooling device 1 according to the present invention is provided in a water-cooled internal combustion engine mounted on a vehicle. The internal combustion engine disposed in the front part of the vehicle includes an engine body in which a water jacket is formed, and the radiator 2 constituting the cooling device 1 is disposed in front of the engine body.

  The cooling device 1 for cooling the cooling water of the water jacket that has become a high temperature by cooling the engine body is a heat dissipation device in which cooling water as a cooling fluid from the water jacket flows. A radiator 2, a cooling fan 3 that generates cooling air for promoting heat dissipation from the cooling water flowing through the radiator 2, a shroud 4 that covers the cooling fan 3, and an electric motor that drives the cooling fan 3 The brushless motor 5 includes a control device 6 having a heat sink 65 that dissipates heat generated by the circuit element group C that constitutes a control circuit that controls the operation of the brushless motor 5.

  The radiator 2 includes an inlet tank 21 having an inlet portion 21a to which an inlet conduit for guiding high-temperature cooling water from the engine body to the radiator 2 is connected, and a number of flat heat transfer tubes into which the cooling water in the inlet tank 21 flows. A radiator core 22 as a heat radiating core having 22a, and an outlet tank 23 in which cooling water having a low temperature after being radiated to the cooling air by the radiator core 22 flows in from each heat transfer tube 22a and gathers. Therefore, the cooling water after radiating heat in the heat transfer tube 22a flows into the outlet tank 23 in a liquid state as cooling water having a temperature lower than that of the cooling water in the inlet tank 21. The outlet tank 23 has an outlet 23a to which an outlet conduit for guiding the low-temperature cooling water from the radiator 2 to the water pump is connected.

  A radiator core 22 disposed between the inlet tank 21 and the outlet tank 23 is provided with a support plate that forms part of the walls of the tanks 21 and 23 so that the tanks 21 and 23 communicate with each other. A tank support plate 23b is shown.) In addition to each heat transfer tube 22a connected in a liquid-tight manner, the outer surface of each heat transfer tube 22a is brazed to promote heat transfer from each heat transfer tube 22a to the cooling air. The heat transfer fins 22b are attached and contacted.

  The cooling fan 3 includes a boss portion 31 that is drivingly connected to the brushless motor 5, a plurality of blades 32 that extend in a radial direction from the boss portion 31 and are connected to the boss portion 31 by integral molding, and an outer end portion of each blade 32. An annular outer ring 33 that joins each other is an axial flow fan that is integrally formed of synthetic resin. The cooling fan 3 is disposed downstream of the radiator core 22 with respect to the cooling air so as to face the radiator core 22 in a direction in which the rotation center line L of the cooling fan 3 extends (hereinafter referred to as “rotation center line direction”). Then, by sucking the cooling air that has passed through the radiator core 22, and hence the cooling air, the cooling air flowing into the radiator core 22 from the upstream side is generated.

  Then, the cooling water that has cooled the engine body flows out of the water jacket and flows into the inlet tank 21, and then is cooled by cooling air in the middle of passing through each heat transfer tube 22a to become a low temperature. Into 23. The low-temperature cooling water in the outlet tank 23 is pumped by the water pump and supplied to the water jacket of the engine body to cool the engine body that is heated by combustion heat.

  By the way, the shroud 4 that forms the air guide path between the radiator 2 and the cooling fan 3 has a rectangular outer peripheral edge and is positioned on the downstream side of the holding portion 41 and the holding portion 41 that holds the radiator 2. And a cylindrical cover portion 42 that covers the outer side of the cooling fan 3 in the radial direction. The holding part 41 is formed of a metal plate material, and the cover part 42 is integrally formed with a synthetic resin together with a flange 43 for attaching the cover part 42 to the holding part 41.

  The brushless motor 5 includes a holder 51 coupled and fixed to the shroud 4, a stator 52 fixed to the holder 51, and a support shaft 53 a that is rotatably supported by the stator 52 via a bearing and has an outer peripheral portion. And a rotor 53 coupled to the boss 31 so as to be integrally rotatable.

  The control device 6 is divided into a first control unit 61 that controls the rotational speed of the brushless motor 5 and a second control unit 62 that turns on and off the current to the amateur coil in response to a command from the first control unit 61. The And the 1st, 2nd control parts 61 and 62 are arrange | positioned in the cooling device 1 in the state which mutually separated in the site | part which does not overlap with the cooling fan 3 seeing from a rotation center line direction. In addition, wiring is typically shown with the dashed-two dotted line in FIG.

  Referring also to FIG. 2, the first control unit 61 attached to the holding unit 41 at a position closer to the outlet tank 23 than the rotation center line L is a circuit board, an integrated circuit, an electrolytic capacitor, etc. housed in the case 61a. Has a first circuit element group 63 composed of a large number of electronic components. On the other hand, the second control unit 62 attached to the outlet tank 23 has a second circuit element group 64 composed of a plurality of electronic components including a circuit board, a power transistor, a shunt resistor and the like housed in the case 62a. . Therefore, the first and second circuit element groups 63 and 64 constitute the circuit element group C constituting the control circuit.

Further, the heat generation amount of the second circuit element group 64 is larger than the heat generation amount of the first circuit element group 63. For this reason, the second control unit 62 includes a heat sink 65 that radiates heat generated by the second circuit element group 64.
The heat sink 65 is disposed in a portion of the radiator 2 of the cooling device 1 that does not overlap with the cooling fan 3 when viewed from the direction of the rotation center line in the outlet tank 23 in the direction of the rotation center line. It is liquid-tightly attached to the side wall 23c via a seal member 66.

  Referring to FIGS. 2 and 3, the heat sink 65 made of a metal having a high thermal conductivity includes a base 65a to which a plurality of power transistors constituting the second circuit element group 64 are attached via a circuit board, and a base 65a. It has heat radiation fins 65b as heat radiation protrusions that constitute a heat radiation part that protrudes into the outlet tank 23 and contacts the cooling water in the outlet tank 23. The radiating fins 65b extend through the outlet tank 23 through a through hole provided in the wall 23c.

  The heat radiating fins 65b are arranged on the extension of the heat transfer tube 22a in the flow direction of the cooling water in the heat transfer tube 22a with respect to at least one heat transfer tube 22a, preferably a plurality of heat transfer tubes 22a. The low-temperature cooling water flowing into the outlet tank 23 from 22a is in a position where it collides on the extension of the heat transfer tube 22a.

  On the other hand, since the first control unit 61 is attached to the metal holding unit 41 (see FIG. 1), the holding unit 41 is a heat sink 65 that dissipates heat generated by the first circuit element group 63.

Next, operations and effects of the embodiment configured as described above will be described.
The entire heat sink 65 of the second control unit 62 that controls the brushless motor 5 that drives the cooling fan 3 is disposed in a portion of the radiator 2 that does not overlap the cooling fan 3 when viewed from the rotational center line direction. By having the radiating fins 65b in contact with the cooling water in the tank 23, the entire heat sink 65 is not exposed to the cooling air in the rotation center line direction in the projection area of the cooling fan 3 in the rotation center line direction. Since the generation of the vortex by the heat sink 65 is greatly reduced, the aerodynamic noise due to the generation of the vortex is greatly reduced and the air volume of the cooling fan 3 is increased. Furthermore, since the heat generated by the second circuit element group 64 is radiated to the low-temperature cooling water after being radiated by the radiator core 22 through the heat sink 65, the heat is radiated to the cooling water before radiating heat from the radiator core 22. In comparison, the heat dissipation amount increases and the heat dissipation performance of the heat sink 65 is improved, so that the heat sink 65 can be downsized.

  The circuit element group C of the control device 6 includes a first circuit element group 63 and a second circuit element group 64 that generates a larger amount of heat than the first circuit element group 63. The control device 6 includes the first circuit element group 63. It is divided into a first control unit 61 having a group 63 and a second control unit 62 having a second circuit element group 64, and the second control unit 62 has a heat sink 65, so that heat is generated in the circuit element group C. The second circuit element group 64, which is a part of the circuit element group having a large amount and high cooling requirement, is separated from the first circuit element group 63, and the heat generated by the second circuit element group 64 passes through the heat sink 65 to the outlet tank. Since the heat is radiated to the cooling water in 23, each of the first and second circuit element groups 63 and 64 is compared with the case where one heat sink is used for the first and second circuit element groups 63 and 64. The heat sink 65 is downsized after the required cooling performance is secured. As a result, the required cooling performance of the circuit element group C is ensured and the heat sink 65 can be downsized.

  The radiator core 22 has a heat transfer tube 22a connected to the outlet tank 23. The heat radiating portion of the heat sink 65 is composed of heat radiating fins 65b protruding into the outlet tank 23, and the heat radiating fins 65b are connected to the heat transfer tube 22a. Due to the position where the cooling water collides on the extension of the heat transfer tube 22a, the low-temperature cooling water flowing into the outlet tank 23 from the heat transfer tube 22a radiates heat by inertia when flowing into the outlet tank 23 from the heat transfer tube 22a. Since the temperature boundary layer collides with the fin 65b, the temperature boundary layer becomes extremely thin, the amount of heat radiation in the heat radiation fin 65b increases due to contact with the low-temperature cooling water, and the heat radiation performance of the heat sink 65 is improved. Can be realized.

Hereinafter, an embodiment in which a part of the configuration of the above-described embodiment is changed will be described with respect to the changed configuration.
The cooling device 1 may be provided in an internal combustion engine used other than the vehicle, and may be provided in a device other than the internal combustion engine, for example, an air conditioner. When the air conditioner is provided, the heat radiating device is a condenser that condenses the refrigerant as the cooled fluid that radiates the cooling air, and the refrigerant in the gaseous state in the inlet tank dissipates heat when it flows through the heat transfer tube. It condenses and flows into the outlet tank from the heat transfer tube in a liquid state.

  The heat radiating protrusion may be constituted by one or a plurality of cylindrical heat radiating pins. In this case as well, as in the above-described embodiment, each pin is a cooling water or liquid from the heat transfer tube 22a. The heat radiation effect can be further enhanced by being in a position where the cooled fluid in a state of collision collides.

  The electric motor may be a motor other than the brushless motor 5. The second control unit 62 may have a second circuit element made of a single electronic component. Further, the holding part 41 and the cover part 42 may be integrally formed of synthetic resin. The cooling fan 3 may be a fan that is disposed upstream of the radiator 2 so as to face the radiator core 22 in the direction of the rotation center line and sends the pressure-fed cooling air to the cooling air.

It is the figure which showed embodiment of this invention and looked at the cooling device based on this invention from the downstream of the cooling air. It is the II-II sectional view taken on the line of FIG. It is the III-III sectional view taken on the line of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Cooling device, 2 ... Radiator, 3 ... Cooling fan, 4 ... Shroud, 5 ... Brushless motor, 6 ... Control device, 21 ... Inlet tank, 22 ... Radiator core, 23 ... Outlet tank, 61 ... 1st control part, 62 ... 2nd control part, 63 ... 1st circuit element group, 64 ... 2nd circuit element group, 65 ... Heat sink, 65b ... Radiation fin, L ... Rotation center line, C ... Circuit element group.

Claims (3)

A heat dissipating device having a heat dissipating core through which the fluid to be cooled flows and an outlet tank into which the liquid to be cooled flows after being radiated to the cooling air by the heat dissipating core, and driving a cooling fan that generates the cooling air A cooling device comprising: an electric motor that performs heat control; and a control device that includes a heat sink that dissipates heat generated by a circuit element group that constitutes a control circuit that controls the electric motor.
The entire heat sink is disposed at a portion that does not overlap the cooling fan when viewed from the rotation center line direction of the cooling fan, and the heat sink has a heat radiating portion that contacts the fluid to be cooled in the liquid state in the outlet tank. A cooling device comprising:   The circuit element group includes a first circuit element group and a second circuit element or a second circuit element group that generates a larger amount of heat than the first circuit element group, and the control device includes the first circuit element group. The first control unit having a group and the second control unit having the second circuit element or the second circuit element group are divided, and the second control unit has the heat sink. The cooling device as described. The heat dissipating core is connected to the outlet tank and has a heat transfer tube through which the fluid to be cooled flows, and the heat dissipating part is composed of a heat dissipating protrusion protruding into the outlet tank. The cooling device according to claim 1 or 2, wherein the fluid to be cooled from the heat transfer tube is in a position where the fluid to be cooled collides on an extension of the heat transfer tube.

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