JP2013180741A - Underguard for vehicle and cooling structure of electric vehicle having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology capable of cooling an inverter of an electric vehicle without elongating a cooling circuit.SOLUTION: An underguard 21 for a vehicle includes a plate-like underguard body 22 having an upper surface and a lower surface, and a refrigerant conduit 33 constituting a part of a cooling structure 30 and installed in the underguard body 22, and is attached along a bottom surface of a vehicle body 11 of a vehicle provided with the cooling structure 30.

Description

  The present invention relates to an under guard for an automobile that is attached along the bottom of a car body of the automobile.

  In a general automobile equipped with an engine (internal combustion engine), an engine and a cooling structure for cooling the engine are accommodated in a space (bonnet) defined in the front part of the vehicle body. The engine cooling structure includes a radiator, a cooling circuit (specifically, a hose) for cooling water that circulates through the engine and the radiator, and components such as a cooling water pump. These components are housed together in the internal space of the bonnet. Is done.

  Some hybrid electric vehicles including a motor that drives an engine and wheels include a cooling structure for cooling an inverter that supplies electric power to the motor. As an inverter cooling structure, one disclosed in JP 2010-184633 A (Patent Document 1) is known. The cooling structure described in Patent Document 1 cools an inverter by circulating cooling water through a cooling water circulation path extending through the inverter.

JP 2010-184633 A

  However, the conventional inverter cooling structure has the following problems. That is, since the arrangement of the inverter is freely designed in the electric vehicle, the inverter may be arranged outside the hood, for example, at the rear portion of the vehicle body or at the center portion in the front-rear direction of the vehicle body. In this case, if the cooling structure parts such as the radiator are arranged in the internal space of the bonnet, the forward path and the return path of the cooling circuit must be installed to the inverter far from the bonnet, and the cooling circuit becomes long.

  In view of the above-described circumstances, a first object of the present invention is to provide a technique capable of cooling an inverter of an electric vehicle without lengthening a pipe line constituting the cooling circuit. In addition, the present invention provides a technology for shortening a cooling circuit in a cooling structure capable of cooling a motor supplied with power from an inverter and other auxiliary devices electrically connected to the inverter, not limited to an inverter. This is the second purpose.

  For this purpose, an automobile underguard according to the present invention is an underguard attached along the bottom of a vehicle body having a cooling structure, and is a plate-like underguard body having an upper surface and a lower surface, and a part of the cooling structure. And a refrigerant pipe provided in the underguard body.

  According to the present invention, the cooling circuit for cooling the inverter can be shortened by attaching the vehicle underguard to the bottom surface of the vehicle body directly under the inverter. The under guard for automobiles of the present invention is not limited to an inverter, and can be used for cooling a motor for driving wheels, cooling other auxiliary machines, and cooling an engine. Moreover, the under guard for motor vehicles of this invention can be attached in arbitrary positions if it is a vehicle body bottom face.

  As one embodiment of the present invention, the refrigerant pipe is attached along the upper surface of the underguard body. As another embodiment, the refrigerant conduit may be provided between the upper surface and the lower surface of the underguard body. For example, the underguard body is made of resin, and the refrigerant pipe is made of a material different from that of the underguard body and is embedded in the underguard body. Thereby, a refrigerant pipe line is arranged between the upper surface and the lower surface of the underguard body. Alternatively, the refrigerant conduit is integrally formed with the underguard body. Thereby, a refrigerant line is formed inside the underguard body.

  As a preferred embodiment of the present invention, the automobile underguard further includes a plurality of fins provided on the lower surface of the underguard body. According to this embodiment, since the surface area of the lower surface is increased to receive the traveling wind, the heat dissipation performance of the underguard for automobiles is improved. As another embodiment, the lower surface of the underguard body is a flat surface or curved surface having no unevenness.

  As a more preferred embodiment, the fin extends in parallel with the longitudinal direction of the vehicle body of the automobile. According to this embodiment, since a driving | running | working wind flows along a fin, the air resistance during driving | running | working of a motor vehicle can be reduced.

  An electric vehicle cooling structure using an underguard for an automobile according to the present invention is a cooling structure for cooling a cooling object mounted on a vehicle body, and the cooling object includes an inverter that supplies electric power to a motor that drives wheels. Including. The cooling structure includes the above-described automobile underguard disposed on the bottom surface of the vehicle body to be cooled, one end connected to the outlet of the refrigerant pipe of the automobile underguard, and the other end connected to the inlet of the refrigerant pipe. The central portion extends through the object to be cooled, and includes a cooling conduit that forms a cooling circuit together with the refrigerant conduit, and pump means provided in the middle of the cooling conduit. According to this embodiment, the cooling circuit that cools the cooling target such as an inverter mounted on the vehicle body can be shortened.

  The cooling structure of the electric vehicle of the present invention may cool only the inverter, may cool the inverter and the motor, or may cool other auxiliary equipment that is electrically connected to the inverter. You may do. As one embodiment, the object to be cooled may further include a device that converts the regenerative energy of the motor into heat energy.

  As described above, the present invention can shorten the cooling pipeline in a cooling structure for cooling a device having a large heat generation amount arranged outside the internal space of the hood, such as an inverter. In addition, it is possible to dissipate the refrigerant at the bottom of the vehicle body through which the traveling wind passes, and it is possible to efficiently cool a device having a large heat generation amount such as an inverter. In addition, the radiator having the cooling structure arranged in the internal space of the bonnet is not necessary, which contributes to the miniaturization of the internal space and the effective use of the empty space. Further, the cooling pipeline can be shortened, and the maintenance performance of the cooling structure is improved.

It is a bottom view which shows the vehicle which comprises the under guard for motor vehicles which becomes one Example of this invention. It is a bottom view which shows typically the underguard for motor vehicles of the Example. It is a longitudinal cross-sectional view which shows the underguard for motor vehicles of the Example. It is a longitudinal cross-sectional view which shows the underguard for motor vehicles of a modification.

  Hereinafter, embodiments of the present invention will be described in detail based on examples shown in the drawings.

  FIG. 1 is a bottom view showing a vehicle including an automobile underguard according to an embodiment of the present invention. FIG. 2 is a bottom view schematically showing the automobile underguard of the embodiment. FIG. 3 is a longitudinal sectional view showing the automobile underguard of the embodiment. The bottom surface of the vehicle body 11 is covered with an under guard 21. The under guard 21 includes a front under guard 21f, a center under guard 21c, and a rear under guard 21r. These under guards 21f, 21c, and 21r may be integrally formed to constitute a single under guard 21, or may be separate from each other or may be further divided. The under guard 21 has a role of reducing the air resistance of the vehicle body 11 and a role of protecting the bottom surface of the vehicle body 11 from an external impact, and has a heat dissipation effect as described later.

  As shown in FIG. 2, the underguard 21 includes a plate-like underguard body 22 having an upper surface and a lower surface, and a refrigerant pipe 33 that is attached and fixed to the upper surface of the underguard body 22 as will be described in detail later. The refrigerant pipe 33 extends so as to reciprocate along the underguard body 22. A plurality of fins 23 are formed on the lower surface of the underguard body 22. As shown in FIG. 1, the fins 23 extend in the front-rear direction of the vehicle body 11.

  The underguard body 22 and the fins 23 are made of aluminum or an aluminum alloy, and the fins 23 are formed by pressing. Aluminum or the like is light and strong, and has a high heat conductivity, so it has a high heat dissipation effect. Alternatively, the underguard body 22 may be formed by die casting together with the fins 23. In addition, the underguard body 22 may be resin-molded together with the fins 23.

  An inverter 12 indicated by a broken line is mounted at the center of the vehicle body 11. The inverter 12 is located immediately above the center underguard 21c. Although not shown, the vehicle body 11 is equipped with a motor that drives the wheels 13 and a battery that supplies power to the inverter 12.

  The inverter 12 converts direct current supplied from the battery into alternating current, and supplies power to the motor mounted on the vehicle body 11. As a result, the inverter 12 freely changes the output and rotation speed of the motor, and drives the wheels 13 with this motor. All four wheels 13 arranged on the front, rear, left and right of the vehicle body 11 may be driven by a motor. Alternatively, an engine (not shown) may be further mounted on the hood at the front of the vehicle body 11, and the wheels 13 may be driven by engine output and motor output.

  Since the inverter generates a large amount of heat, a cooling structure 30 is attached to the inverter 12 as shown in FIG. The cooling structure 30 includes a cooling circuit 31 that is a conduit that goes around via the inverter 12 and the underguard 21. The cooling circuit 31 includes a cooling pipe 32 provided above the bottom surface of the vehicle body 11 and a refrigerant pipe 33 provided in the center underguard 21c. One end 32 m of the cooling pipe 32 extends to the bottom surface of the vehicle body 11 and is connected to the outlet of the refrigerant pipe 33. The other end 32 n of the cooling pipe 32 also extends to the bottom surface of the vehicle body 11 and is connected to the inlet of the refrigerant pipe 33. The central portion of the cooling pipe 32 extends via the inverter 12. A pump 34 is installed in the middle of the cooling pipe 32. The pump 34 causes the refrigerant to flow along the cooling circuit 31 and circulates between the inverter 12 and the underguard 21. The pump 34 may be driven by a motor that drives the wheels 13, or may be driven by a motor other than this motor.

  According to the cooling structure 30 of the present embodiment, the underguard 21 functions as a radiator having a heat dissipation effect, and the refrigerant flowing through the refrigerant pipe 33 can be cooled. Then, the cooled refrigerant can be sent to the inverter 12 along the cooling pipe 32 to cool the inverter 12. Thereafter, the refrigerant again flows into the refrigerant pipe 33 and circulates along the cooling circuit 31.

  Further, according to the present embodiment, since the underguard body 22 has the plurality of fins 23 formed on the lower surface thereof, the heat dissipation effect of the underguard 21 is enhanced. In addition, since the fins 23 extend in parallel with the longitudinal direction of the vehicle body, the traveling wind flows along the fins, and the air resistance of the vehicle body 11 can be reduced.

  Next, a modification of the present invention will be described. FIG. 4 is a cross-sectional view schematically showing a modification of the present invention. With respect to this modification, the same reference numerals are given to the configurations common to the above-described embodiments, and the description thereof will be omitted, and different configurations will be described below. The refrigerant conduit 33 of this modified example is provided between the upper surface and the lower surface of the underguard body 22.

  The underguard body 22 and the fins 23 are made of resin. On the other hand, the refrigerant pipe 33 is made of aluminum or an aluminum alloy. The refrigerant pipe 33 is insert-molded so as to be embedded between the upper surface and the lower surface of the underguard body 22.

  Although not shown, in the modification shown in FIG. 4, the entire underguard 21 may be made of aluminum or aluminum alloy, and the underguard body 22 and the refrigerant pipe 33 may be integrally formed by die casting.

  The cooling pipe 32 passes through the inverter 12 and the heat conversion device 15. When the battery is charged by regenerative operation of the motor, the heat conversion device 15 converts the regenerative energy of the motor into heat energy if the battery is fully charged.

  According to the cooling structure 30 of the modified example shown in FIG. 4, the inverter 12 and the heat conversion device 15 that is an auxiliary machine related to the inverter can be cooled. In addition, since the under guard 21 is disposed directly below the inverter 12 and the heat conversion device 15, the cooling pipe 32 can be shortened.

  Although the embodiments of the present invention have been described with reference to the drawings, the present invention is not limited to the illustrated embodiments. Various modifications and variations can be made to the illustrated embodiment within the same range or equivalent range as the present invention. For example, as indicated by a broken line in FIG. 1, the inverter 14 may be mounted on the rear portion of the vehicle body 11, and the rear underguard 21 r positioned immediately below the inverter 14 may include a refrigerant pipe. Alternatively, the front underguard 21f may be provided with a refrigerant pipe to cool an inverter or the like directly above the front underguard 21f. Although not illustrated, the cooling target of the cooling structure 30 may be the inverter 12 and the motor, or may be a motor instead of the inverter 12.

  The cooling structure for an electric vehicle according to the present invention is advantageously used in an electric vehicle and a hybrid vehicle.

  11 Car body, 12 Inverter, 13 Wheel, 14 Inverter, 15 Heat conversion device, 21 Under guard, 21f Front under guard, 21c Center under guard, 21r Rear under guard, 22 Under guard body, 23 Fin, 30 Cooling structure, 31 Cooling circuit, 32 Cooling line, 33 Refrigerant line.

Claims (8)

An under guard that is attached along the bottom of a vehicle body having a cooling structure,
A vehicle underguard comprising: a plate-like underguard body having an upper surface and a lower surface; and a refrigerant pipe constituting a part of the cooling structure and provided in the underguard body.   The automobile underguard according to claim 1, wherein the refrigerant pipe is attached along an upper surface of the underguard body.   The automobile underguard according to claim 1, wherein the refrigerant pipe is provided between an upper surface and a lower surface of the underguard body.   The automobile underguard according to claim 3, wherein the underguard body is made of resin, and the refrigerant pipe is made of a material different from that of the underguard body and embedded in the underguard body.   The automobile underguard according to claim 1, further comprising a plurality of fins provided on a lower surface of the underguard body.   The automobile underguard according to claim 5, wherein the fin extends in parallel with a longitudinal direction of the automobile body. A cooling structure for cooling a cooling target mounted on a vehicle body,
The object to be cooled includes an inverter that supplies electric power to a motor that drives a wheel,
The vehicle under guard according to any one of claims 1 to 6, wherein the vehicle under guard is disposed on a bottom surface of the vehicle body immediately below the object to be cooled.
One end is connected to the outlet of the refrigerant line of the under guard for the automobile, the other end is connected to the inlet of the refrigerant line, the central portion extends through the object to be cooled, and the cooling circuit is connected with the refrigerant line. A cooling pipe to be configured; and
A cooling structure for an electric vehicle, comprising: pump means provided in the middle of the cooling pipe.   The cooling structure for an electric vehicle according to claim 7, wherein the object to be cooled further includes a device that converts regenerative energy of the motor into heat energy.

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