JP4832225B2 - Cooling structure for electrical equipment in vehicles - Google Patents

Description

  The present invention relates to a vehicle in which an electric device including a battery for driving a traveling motor, a DC / DC converter, and a motor driving inverter is disposed below a floor behind the seat, and the electric device is cooled by cooling air. The present invention relates to a cooling structure for electrical equipment.

  A power supply device including a battery for driving a motor for driving an automobile is mounted in a trunk room behind a rear seat, and the battery is cooled by cooling air supplied by a forced blower provided integrally with the power supply device. Is known.

In addition, a battery, a DC / DC converter, a battery that drives a motor for driving a vehicle, a DC / DC converter, an inverter for driving a motor, a cooling fan, and the like are arranged below the rear seat, and the battery and the DC / DC converter are cooled by the cooling air sucked by the cooling fan. Further, it is known from Patent Document 2 below that the motor driving inverter is cooled.
JP 2003-45392 A JP 2005-153827 A

  By the way, although what was described in the said patent document 1 cools the battery of a power supply device with the cooling air which a forced air blower supplies, cooling of the DC / DC converter contained in a power supply device or the inverter for a motor drive is carried out. Is not disclosed.

  In addition, what is described in Patent Document 2 is that a battery, a DC / DC converter, a motor driving inverter, and a cooling fan are arranged in series in the vehicle width direction, and the battery, the DC / DC converter are cooled by cooling air sucked by the cooling fan. And the motor drive inverter is cooled sequentially.

  In this case, the cooling air gradually increases in temperature by heat exchange while cooling the battery, the DC / DC converter, and the motor driving inverter. Therefore, even if the upstream battery can be sufficiently cooled, the downstream motor There is a possibility that the drive inverter cannot be sufficiently cooled. In addition, since the battery, DC / DC converter, motor drive inverter and cooling fan are arranged in series, the size of the power supply device becomes long, which not only greatly restricts the mounting on the vehicle, but also reduces the amount of cooling air. There is a problem that a large and high-performance cooling fan is required because the passage resistance of the passage increases.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to improve the cooling performance while avoiding an increase in size of an electric device disposed below a floor behind a seat so as to drive a traveling motor. To do.

In order to achieve the above object, according to the first aspect of the present invention, an electric device including a battery for driving a traveling motor, a DC / DC converter, and a motor driving inverter is mounted on the floor behind the seat. A cooling structure for an electric device in a vehicle which is disposed below and cools the electric device with cooling air, wherein the DC / DC converter and the motor driving inverter are juxtaposed in the vehicle width direction above the battery. Cooling air that flows from the front to the rear flows in the power supply unit storage chamber provided with the battery, the DC / DC converter, and the motor drive inverter in an up-and- down manner , and the lower battery and the upper DC / DC. cooling the converter and the motor driving inverter in parallel, to the power supply unit accommodating chamber of the housing chamber, before Battery is characterized in that a gradual squeezing air guide plate toward the downstream end of the flow path cross-sectional area of the downstream half of the portion arranged, the cooling structure of electric devices in a vehicle is proposed.

  According to the invention described in claim 2, in addition to the configuration of claim 1, a high-voltage switchboard is arranged on one side in the vehicle width direction of the battery, and the extending portion of the high-voltage switchboard is connected to the upper end of the battery. A cooling structure for an electric device in a vehicle is proposed, characterized in that it extends upward and the extension portion is connected to a smoothing capacitor provided in the DC / DC converter or the motor drive inverter.

  According to a third aspect of the present invention, in addition to the configuration of the second aspect, the contactor for cutting off the current from the battery is disposed on the high-voltage switchboard, and cooling of the electrical equipment in the vehicle is provided. A structure is proposed.

According to a fourth aspect of the present invention, in addition to the configuration of any one of the first to third aspects, the DC / DC converter and the motor drive inverter are fixed to a vehicle body. A cooling structure for an electric device in a vehicle is proposed, which is housed in a metal case and the battery is supported on the lower surface of the metal case.

  The rear seat 16 of the embodiment corresponds to the seat of the present invention, the power supply unit 19 of the embodiment corresponds to the electric device of the present invention, and the rear floor 27 of the embodiment corresponds to the floor of the present invention. The battery module 37 of the embodiment corresponds to the battery of the present invention, and the lower metal case 45 and the upper metal case 46 of the embodiment correspond to the metal case of the present invention.

According to the configuration of the first aspect, among the electric devices disposed below the floor behind the seat to drive the traveling motor, the battery is disposed in the lower part, and the DC / DC converter and the motor drive are disposed in the upper part. Since the inverters are juxtaposed in the vehicle width direction, the cooling air flowing from the front to the rear of the vehicle can be divided into upper and lower parts to cool the lower battery, the upper DC / DC converter and the motor drive inverter in parallel. It becomes. This not only simplifies the passage of the cooling air, downsizes the entire electrical equipment and enhances the mountability to the vehicle body, but also lowers the temperature before heat exchange in all of the battery, the DC / DC converter and the motor drive inverter. The cooling air can be applied to increase the cooling effect, and the pressure loss of the cooling air can be reduced. Further, in particular, the power supply unit storage chamber is provided with a baffle plate that gradually narrows the flow path cross-sectional area of the downstream half of the storage chamber in the downstream portion of the battery to the downstream end, so that it is difficult to be cooled. The downstream battery can be efficiently cooled, and the battery can be uniformly cooled.

  According to the second aspect of the present invention, the DC / DC converter or the motor drive inverter is provided with an extending portion that extends upward from the upper end of the battery to the high-voltage switchboard disposed on one side in the vehicle width direction of the battery. Therefore, the cables connecting the high-voltage switchboard, the smoothing capacitor, the DC / DC converter, and the motor driving inverter can be eliminated or minimized.

  According to the third aspect of the present invention, since the contactor that cuts off the current from the battery is disposed on the high-voltage switchboard, the cable that connects the battery, the contactor, and the electric device can be eliminated or minimized.

  According to the fourth aspect of the present invention, the DC / DC converter and the motor drive inverter are housed in a common metal case fixed to the vehicle body, and the battery is supported on the lower surface of the metal case. A DC / DC converter and a motor that can not only effectively block electrical noise generated from an inverter for driving a motor with a metal case, but also have a relatively heavy battery placed on the lower side and a relatively light weight. The driving inverter can be arranged on the upper side to improve the stability of the vehicle body.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  1 to 9 show an embodiment of the present invention. FIG. 1 is an overall side view of a hybrid vehicle, FIG. 2 is an enlarged view of a main part of FIG. 1, and FIG. 3 is an exploded perspective view of a resin case and a power unit. 4 is an exploded perspective view of the power supply unit, FIG. 5 is a view taken in the direction of arrow 5 in FIG. 2, FIG. 6 is a cross-sectional view taken along line 6-6 in FIG. 8 is a cross-sectional view taken along line 8-8 in FIG. 7, and FIG.

  As shown in FIGS. 1 and 2, a hybrid vehicle using an unshown engine and motor as a driving source for driving includes a front seat 13 including a seat cushion 11 and a seat back 12, and a seat cushion 14 and a seat back 15. And a rear seat 16. A fuel tank 17 is disposed below the seat cushion 11 of the front seat 13, and a power supply unit 19 for driving the motor is mounted below the luggage space 18 behind the rear seat 16.

  A pair of left and right stays 20, 20 are foldably provided on the lower surface of the seat cushion 14 of the rear seat 16. When the rear seat 16 is in use, the lower ends of the stays 20, 20 are provided on the lower seat floor 21 of the rear seat 16. The rear end of the seat cushion 14 is locked to the hooks 22 and 22 and is fixed to the seat cushion locking portion 24 provided on the raised portion 23 on the rear side of the lower seat floor 21. The seat back 15 can fall forward through a reclining shaft 25 provided at the rear end of the seat cushion 14.

  Accordingly, when the rear end of the seat cushion 14 is separated from the seat cushion locking portion 24 of the raised portion 23, the stays 20 and 20 swing forward with the hooks 22 and 22 serving as fulcrums, thereby causing the seat cushion 14 to move under the seat. It sinks while parallelly moving forward and downward to a position along the floor 21. Then, by swinging the seat back 15 forward about the reclining shaft 25, the rear seat 16 is folded so that the seat back 15 becomes substantially horizontal (see the chain line in FIG. 2).

  A power supply unit storage portion 26 recessed downward is continuous behind the raised portion 23 on the rear side of the under-seat floor 21, and the periphery of the upper surface opening of the power supply unit storage portion 26 constitutes the floor of the luggage space 18. Covered with a rear floor 27 (see FIG. 5).

  Next, the structure of the power supply unit 19 is demonstrated based on FIGS.

  The casing that houses the power supply unit 19 is composed of a container-shaped lower resin case 31 and a generally flat lid-shaped upper resin case 32. At the front of the lower resin case 31, there are three duct-shaped cooling air intake passages 31a to 31c that open toward the front of the vehicle body, and a duct-shaped cooling air intake passage 31d that opens toward the left side of the vehicle body. Two integrally formed cooling air discharge passages 31e and 31f extending in the vehicle width direction are formed in the rear portion of the lower resin case 31 while being integrally formed.

  The cooling air intake passages 31a to 31c open at the rear end of the seat cushion 14 of the rear seat 16, and suck air in the vehicle compartment through the lower surface of the seat cushion 14 (see FIG. 6). The cooling air intake passage 31d opens at the side of the seat cushion 14 of the rear seat 16 and sucks air in the passenger compartment therefrom. The bowl-shaped cooling air discharge passages 31e and 31f constitute a duct by cooperation with the upper resin case 32 coupled to the upper surface thereof.

  A wind guide plate 33 is fixed horizontally in the middle of the lower resin case 31, and a cooling fan 34 formed of an axial fan is driven by a motor support bracket 33 a formed integrally with the rear portion of the wind guide plate 33. The cooling fan drive motor 35 is supported (see FIG. 6). The lower case 31 is narrowly wrapped at the position of the cooling fan 34, a large-capacity power supply unit storage chamber 36 is formed on the front side thereof, and the cooling air discharge passages 31e and 31f communicate with the rear side thereof. Accordingly, the cooling air guided rearward through the cooling fan 34 branches into the left and right cooling air discharge passages 31e and 31f.

  The power supply unit 19 includes a total of 12 cylindrical battery modules 37 arranged in four rows and three stages, and these battery modules 37 are divided into four parts in the vertical direction with two bolts 38 and 38. The battery holders 39 are sandwiched between two sets of left and right battery holders 39. At this time, the air guide plate 40 is laminated on the lower surface of the lowermost battery holder 39 and fastened together with the bolts 38 (see FIG. 8). The upper surface of the air guide plate 40 facing the lowermost battery modules 37 is inclined so that the rear side is higher, that is, closer to the lowermost battery modules 37.

  Further, the power supply unit 19 converts a DC / DC converter 41 that steps down the high voltage of the battery modules 37... Electrically connected in series to 12 volts, and converts a direct current of the battery modules 37. A motor driving inverter (PDU) 42 for controlling the driving of the motor, an electronic control unit 43 provided on the printed circuit board, and a smoothing capacitor 44 for the motor driving inverter 42. The DC converter 41, the motor drive inverter 42, the electronic control unit 43, and the smoothing capacitors 44 are flat and joined together by a container-like lower metal case 45 having an open upper surface and a plurality of bolts 47 on the upper surface. It is stored in a space defined by a lid-like upper metal case 46. In this way, by storing the high-voltage components that cause electrical noise in the space surrounded by the lower metal case 45 and the upper metal case 46, the influence of electrical noise on other devices is eliminated. be able to.

  The DC / DC converter 41 and the motor drive inverter 42 are juxtaposed on the left and right sides in the vehicle width direction, respectively, and an electronic control unit 43 is disposed above the DC / DC converter 41, and on the upper surface of the motor drive inverter 42. Three smoothing capacitors 44 are arranged.

  The lower metal case 45 is fixed by a plurality of bolts 50 to the lower surfaces of the two power supply unit support frames 49, 49 that bridge the left and right side frames 48, 48 in the vehicle width direction. Further, two sets of left and right battery holders 39 for bundling the battery modules 37 are suspended and supported on the lower surface of the lower metal case 45 by a plurality of bolts 51. At this time, a polystyrene foam insulator 52 is sandwiched between the lower surface of the lower metal case 45 and the upper surface of the uppermost battery module 37.

  Thus, in the power supply unit 19, the relatively heavy battery modules 37 are arranged on the lower side, and the DC / DC converter 41 and the motor driving inverter 42, which are lighter than the battery modules 37, are arranged on the upper side of the battery modules 37. Therefore, the center of gravity of the power supply unit 19 can be lowered to improve the stability of the vehicle.

  The lower metal case 45 is formed with an opening 45a facing the lower surface of the DC / DC converter 41 and an opening 45b facing the lower surface of the motor drive inverter 42, and on the upper surface of the insulator 52 facing both the openings 45a and 45b. Two air guide grooves 52a and 52b extending in the front-rear direction are formed (see FIG. 7). A number of cooling fins 41 a projecting from the lower surface of the DC / DC converter 41 pass through the opening 45 a of the lower metal case 45 and project into the air guide groove 52 a of the insulator 52, and project from the lower surface of the motor drive inverter 42. The cooling fins 42 a... Pass through the opening 45 b of the lower metal case 45 and project into the air guide groove 52 b of the insulator 52.

  Further, a step 52c extending in the vehicle width direction is formed on the lower surface of the insulator 52 facing the upper surface of the uppermost battery module 37 ... (see FIG. 8), and the battery module 37 ... The space between the upper surface and the lower surface of the insulator 52 is wide, and the space is narrow on the rear side.

  A rectangular plate-shaped high voltage switchboard 53 is disposed on the right side of the battery modules 37 stacked in three stages. The upper portion of the high-voltage switchboard 53 is an extending portion 53a that extends upward from the upper surface of the uppermost battery module 37, and the left side surface of the extending portion 53a is close to the right side surface of the motor drive inverter 42. And extend to opposite positions. And the extension part 53a of the high voltage switchboard 53 and the smoothing capacitors 44 are connected by a pair of terminals 54, 54. Further, on the right side surface of the high voltage switchboard 53, there are provided a contactor 55 for turning on / off the current from the battery modules 37, and a current sensor 56 for detecting a current flowing into or out of the battery modules 37.

  The power unit 19 configured as described above is housed in the lower resin case 31, and the upper resin case 32 covering the upper surface opening is fixed by a plurality of bolts 57. In this state, the upper resin case 32 is at the same height as the rear floor 27, and they cooperate to form the floor surface of the luggage space 18.

  Next, the operation of the embodiment of the present invention having the above configuration will be described.

  When the driving motor is driven by the current supplied from the power supply unit 19, the battery modules 37,..., The DC / DC converter 41, the motor driving inverter 42, etc. of the power supply unit 19 generate heat. They are cooled by the cooling air generated by driving at.

  As shown in FIG. 6, when the cooling fan 34 rotates, negative pressure is generated in the power supply unit storage chamber 36 defined by the lower resin case 31 and the upper resin case 32, and the vehicle is discharged from the four cooling air intake passages 31 a to 31 d. Indoor air is sucked into the power supply unit storage chamber 36. This cooling air is split up and down inside the power supply unit storage chamber 36 with the insulator 52 as a boundary, and the cooling air that has flowed downward forms gaps between a total of twelve battery modules 37 arranged in four rows and three stages. The battery modules 37 are cooled while flowing backward.

  At this time, as shown in FIG. 8, the air guide plate 40 facing the lower surface of the lowermost battery modules 37... Is inclined rearward and the insulator 52 facing the upper surface of the uppermost battery modules 37. Since the stepped portion 52c is formed on the lower surface, the flow passage cross-sectional area on the downstream side of the power supply unit storage chamber 36 is reduced, and the flow velocity of the cooling air is increased. As a result, the downstream battery modules 37 that are difficult to be cooled can be efficiently cooled, and all the battery modules 37 can be uniformly cooled.

  As shown in FIGS. 6, 7, and 9, the cooling air divided to the upper side of the insulator 52 flows into the left and right air guide grooves 52 a and 52 b formed in the front-rear direction on the upper surface of the insulator 52 and flows from the front to the rear. One of them contacts the cooling fins 41a of the DC / DC converter 41 protruding downward from the opening 45a of the lower metal case 45 to cool the DC / DC converter 41, and the other is the opening 45b of the lower metal case 45. The motor driving inverter 42 is cooled by contacting the cooling fins 42a of the motor driving inverter 42 projecting downward from the motor 42.

  The cooling air that has cooled the power supply unit 19 in this manner merges again and passes through the cooling fan 34, and then branches to the left and right cooling air discharge passages 31 e and 31 f behind the cooling fan 34. The downstream ends of the left and right cooling air discharge passages 31e and 31f branched to the left and right sides in the vehicle width direction flow into the space between the lining of the luggage space 18 and the rear fender, and part of the downstream end is discharged outside the vehicle. Is returned to the passenger compartment. At this time, silencers may be provided in the cooling air discharge passages 31e and 31f so that the exhaust noise is not transmitted to the vehicle interior.

  The power supply unit storage portion 26 formed on the rear floor 27 is a space that is normally used as a spare tire storage portion. By storing the power supply unit 19 using this space, a luggage space 18 behind the rear seat 16 is provided. There is no pressure. In addition, the upper resin case 32 that covers the upper surface opening of the lower resin case 31 that houses the power supply unit 19 is connected to the same plane as the rear floor 27 to form a flat floor surface of the luggage space 18. Will improve.

  In addition, a DC / DC converter 41 and a motor driving inverter 42 are arranged on the upper side of the twelve battery modules 37... And the electronic control unit 43 is supported on the upper part of the DC / DC converter 41 to support the motor. Since the smoothing capacitors 44 are supported on the upper part of the drive inverter 42 and the high-voltage switchboard 53 is arranged on the side surfaces thereof, the power supply unit 19 is made compact and easily housed in the power supply unit housing portion 26 formed on the rear floor 27. Not only can you do this, you can eliminate or minimize the cables that connect them together. For example, by providing the contactor 55 on the high-voltage switchboard 53, the cable connecting the battery modules 37... And the motor drive inverter 42 can be eliminated, or the extension part 53 a can be formed on the high-voltage switchboard 53. The part 53a and the smoothing capacitors 44 can be connected by the terminals 54, 54 without using a cable.

  The cooling air sucked into the power supply unit storage chamber 36 in the lower resin case 31 is divided in the vertical direction, and the lower battery module 37..., The upper DC / DC converter 41 and the motor drive inverter 42 are paralleled. Therefore, the low temperature cooling air before heat exchange can be brought into contact with the battery modules 37,..., The DC / DC converter 41, and the motor driving inverter 42 so as to evenly cool, and the pressure loss of the cooling air is minimized. To the limit. Accordingly, sufficient cooling performance can be ensured by using an inexpensive axial flow fan without using an expensive centrifugal fan (for example, a sirocco fan) for the cooling fan 34.

  If the battery modules 37..., The DC / DC converter 41, and the motor drive inverter 42 are cooled in series, the cooling effect of the devices arranged on the upstream side is improved, but the devices arranged on the downstream side are improved. There is a problem that the cooling effect is lowered, and the pressure loss of the cooling air is increased, so that a high performance fan is required for the cooling fan 34 and the cooling fan drive motor 35, which causes a cost increase. .

  Further, since the cooling air discharge passages 31e and 31f through which the cooling air after passing through the cooling fan 34 branches are bifurcated, a sufficient total cross-sectional area of the cooling air discharge passages 31e and 31f is secured, and the cooling fan The load on the cooling fan drive motor 35 can be further reduced by lowering the back pressure of 34. Moreover, since the cooling air discharge passages 31e and 31f are formed on the lower surface of the upper resin case 32, that is, the lower surface of the rear floor 27, the volume of the luggage space 18 is not compressed.

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.

  For example, in the embodiment, a hybrid vehicle including an engine and a motor as a driving source for traveling is illustrated, but the present invention can also be applied to an electric vehicle including only a motor as a driving source for traveling.

Overall side view of hybrid vehicle 1 is an enlarged view of the main part of FIG. Disassembled perspective view of resin case and power supply unit Exploded perspective view of the power supply unit 5 direction arrow view of FIG. 6-6 sectional view of FIG. Sectional view along line 7-7 in FIG. Sectional view taken along line 8-8 in FIG. Power supply unit cooling action explanatory diagram

16 Rear seat (seat)
19 Power supply unit (electric equipment)
27 Rear floor (floor)
36 power supply unit storage chamber 37 battery module (battery)
40 Air guide plate 41 DC / DC converter 42 Motor drive inverter 44 Smoothing capacitor 45 Lower metal case (metal case)
46 Upper metal case (metal case)
53 High Voltage Switchboard 53a Extension 55 Contactor

Claims (4)

An electric device (19) including a battery (37) for driving the traveling motor, a DC / DC converter (41), and a motor driving inverter (42) is placed below the floor (27) behind the seat (16). A cooling structure for an electrical device in a vehicle, wherein the electrical device (19) is arranged and cooled with cooling air
The DC / DC converter (41) and the motor drive inverter (42) are juxtaposed in the vehicle width direction above the battery (37),
The cooling air flowing from the front to the rear of the vehicle body flows in the power supply unit storage chamber (36) provided with the battery (37), the DC / DC converter (41) and the motor drive inverter (42) in an up and down direction , The lower battery (37), the upper DC / DC converter (41) and the motor drive inverter (42) are cooled in parallel ,
In the power supply unit storage chamber (36), a wind guide for gradually narrowing the flow passage cross-sectional area of the downstream half of the storage chamber (36) where the battery (37) is disposed toward the downstream end. A cooling structure for electric equipment in a vehicle, characterized in that a plate (40) is provided .   A high-voltage switchboard (53) is arranged on one side in the vehicle width direction of the battery (37), and an extension part (53a) of the high-voltage switchboard (53) is extended upward from the upper end of the battery (37), 2. The vehicle according to claim 1, wherein the extension portion (53 a) is connected to a smoothing capacitor (44) provided in the DC / DC converter (41) or the motor drive inverter (42). Cooling structure for electrical equipment.   The cooling structure for electric equipment in a vehicle according to claim 2, wherein a contactor (55) for cutting off a current from the battery (37) is arranged on the high-voltage switchboard (53). The DC / DC converter (41) and the motor drive inverter (42) are accommodated in a common metal case (45, 46) fixed to the vehicle body, and the battery (45, 46) is placed on the lower surface of the metal case (45, 46). 37. The cooling structure for an electric device in a vehicle according to any one of claims 1 to 3 , wherein 37) is supported.

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