Patent Publication Number: US-2016243919-A1

Title: Cooling unit for vehicle battery pack

Description:
INCORPORATION BY REFERENCE 
     The disclosure of Japanese Patent Application No. 2015-031941 filed on Feb. 20, 2015 including the specification, drawings and abstract is incorporated herein by reference in its entirety. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a cooling unit for a vehicle battery pack, especially to a cooling unit having an inlet duct provided with an inlet port that is open upwardly. 
     2. Description of Related Art 
     A battery pack including a battery for driving a motor is mounted on an automobile and a hybrid vehicle. The battery pack generates heat due to discharge and charge, and, since output characteristics of the battery pack are deteriorated at high temperature, air in a vehicle interior is blown by a cooling blower to the battery pack for cooling. 
     A battery pack is arranged at various positions in a vehicle, such as underneath a seat, an underfloor space of a floor panel, and a cargo room, depending on a vehicle structure, a size of the battery pack, and so on. Especially, when a battery pack is arranged in an underfloor space of a floor panel, there are instances where a cooling blower is also arranged in the underfloor space. As a structure in which a cooling blower is arranged in an underfloor space, a structure is known, which is provided with an inlet duct having an inlet port in a floor panel, a cooling blower connected with a downstream end of the inlet duct, and a liquid reservoir that is provided in the inlet duct and retains liquid flown into the inlet duct (for example, Japanese Patent Application Publication No. 2014-129039 (JP 2014-129039 A)). 
     In the structure described in JP 2014-129039 A, since the inlet port is provided in the floor panel, the inlet port is open upwardly. Therefore, in a case where liquid such as beverage is spilled in a vehicle interior, the liquid flows into the inlet duct from the inlet port and the liquid reservoir retains the liquid temporarily. 
     However, when a large amount of liquid flows in the liquid reservoir in excess of its capacity, the liquid reservoir is not able to retain the liquid, and the liquid reaches the cooling blower. This could cause a malfunction of the cooling blower. 
     Even though a liquid inflow amount is not so large, the liquid that has flown in is not necessarily retained in the liquid reservoir, and could reach the cooling blower. Moreover, although the liquid reservoir is provided on the way from the inlet port to the cooling blower, in a case where the cooling blower is arranged immediately below the inlet port, it becomes difficult to provide the liquid reservoir. In such a case, when liquid flows in from the inlet port, the liquid directly reaches the cooling blower. 
     SUMMARY OF THE INVENTION 
     Thus, the invention provides a cooling unit that restrains liquid from flowing into an inlet duct and reduces a malfunction of a cooling blower caused by the liquid. 
     A cooling unit for a vehicle battery pack according to an aspect of the invention is characterized by including a cooling blower configured to blow cooling air to a battery pack mounted on a vehicle, an inlet duct that is connected with the cooling blower and provided with an inlet port opening upwardly, a cover member arranged above the inlet port. The cover member has a top plate configured to be separated upwardly from an end face of the inlet port and configured to cover the inlet port, and a side plate configured to be separated from a side surface of the inlet port and that extends below an end face of the inlet port from a side edge of the top plate, and an opening communicating with the inlet port is formed between the side surface of the inlet port and an inner wall of the side plate. Thus, an intake passage into the inlet port becomes a labyrinth structure, thereby restraining liquid from entering the inlet duct. 
     The top plate may have a sound absorbing member that absorbs operating noise of the cooling blower. 
     A cooling unit for a vehicle battery pack according to another aspect of the invention is characterized by including a cooling blower configured to blow cooling air to a battery pack mounted on a vehicle, an inlet duct that is connected with the cooling blower and provided with an inlet port opening upwardly, and a cover member arranged above the inlet port. The cover member is configured to cover the inlet port such that an intake passage to the inlet port becomes a labyrinth structure. 
     According to the above aspect of the invention, liquid is restrained from flowing into the inlet duct, thereby reducing a malfunction of the cooling blower caused by liquid. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Features, advantages, and technical and industrial significance of exemplary embodiments of the invention will be described below with reference to the accompanying drawings, in which like numerals denote like elements, and wherein: 
         FIG. 1  is a schematic side view of a hybrid vehicle according to an embodiment of the invention; 
         FIG. 2  is a perspective view of a cooling unit and an under body; 
         FIG. 3  is an exploded perspective view of the cooling unit; 
         FIG. 4  is an exploded perspective view of the cooling blower and a floor panel; 
         FIG. 5  is an exploded perspective view of the cooling blower and an inlet duct; 
         FIG. 6  is an enlarged sectional view of the vicinity of an inlet port of the inlet duct; 
         FIG. 7  is an exploded perspective view of an inlet cover; and 
         FIG. 8  is an enlarged sectional view of an engagement part of a cover member. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     First of all, an arrangement position of a battery pack  30 , which includes a battery for supplying electric power to a driving motor for a hybrid vehicle  1 , is explained. As shown in  FIG. 1 , the hybrid vehicle  1  is provided with a vehicle compartment floor panel  10 , which structures a floor of a vehicle compartment  4  where a front seat  2  and a rear seat  3  are arranged, and an under body  20  that structures an under floor space of the vehicle compartment  4 . 
     In the underfloor space between the front seat  2  and the rear seat  3 , the battery pack  30  for supplying electric power to the driving motor is arranged. The battery pack  30  is arranged on the right side in the vehicle-width direction, and a cooling unit  40 , which blows air of the vehicle compartment  4  to the battery pack  30 , is arranged at a position adjacent to the battery pack  30  in the vehicle-width direction, namely, on the left side in the vehicle-width direction. 
     As shown in  FIG. 2 , the under body  20  is provided with a floor tunnel  21  extending longitudinally in a center in the vehicle-width direction, side sills  22  extending longitudinally on both sides in the vehicle-width direction, cross members  23  extending in the vehicle-width direction, and a bottom panel  24  that is a bottom part of an area surrounded by the floor tunnel  21 , the side sills  22 , and the cross members  23 . In  FIG. 2 , arrow FR shows a direction in which the vehicle advances, and arrow UP shows a vehicle upper direction, arrow LH shows the left side in the vehicle advancing direction. A relation among arrows FR, UP, LH is the same in the other drawings. 
     In the under body  20 , two recessed portions  25   a ,  25   b  are formed, which are surrounded by the floor tunnel  21 , the side sills  22 , the cross members  23 , and the bottom panel  24 . The recessed portions  25   a ,  25   b  are positioned between the front seat  2  and the rear seat  3 . 
     The battery pack  30  is housed in the recessed portion  25   a . The cooling unit  40  is housed in the recessed portion  25   b  so that an air-blowing port faces the battery pack  30 . As stated later, the housed cooling unit  40  includes a cooling blower  50  that discharges cooling air, an inlet duct  60  that takes in air of the vehicle interior, and a cooling duct  70  that leads the cooling air to the battery pack  30 , and the cooling blower  50 , the inlet duct  60  and the cooling duct  70  are suspended from and fixed to a floor panel  90  that forms a part of the vehicle compartment floor panel  10 . 
     The floor panel  90  is provided with four mounting holes  93 D for mounting the floor panel  90  onto the cross members  23  of the under body  20 . As stated above, the floor panel  90 , to which the cooling blower  50 , the inlet duct  60 , and the cooling duct  70  are fixed, is fixed to the cross members  23  by four bolts D through the four mounting holes  93 D. An end part of the inlet duct  60  is provided with a mounting hole  64 C for mounting the inlet duct  60  onto the cross member  23  of the under body  20 . Then, the inlet duct  60  is fixed to the cross member  23  by a clip C through the mounting hole  64 C. 
     The cross members  23  are provided with screw holes  23 D, which corresponds to the bolts D for fixing the floor panel  90 , and a fixing hole  23 C, which corresponds to the clip C for fixing the inlet duct  60 . Also, the floor tunnel  21  is provided with a bracket  21   a  having a screw hole  21 D that corresponds to the bolt D for fixing the floor panel  90 . 
     An upper part of the battery pack  30  is covered by another floor panel (not shown) mounted on the cross members  23 . This floor panel also covers an upper part of the cooling duct  70  of the cooling unit  40 . The floor panel  90  of the cooling unit  40  and another floor panel covering the upper part of the battery pack  30  structure a part of the vehicle compartment floor panel  10  of the vehicle compartment  4 . 
     Next, the cooling unit  40  is explained with reference to  FIG. 3  to  FIG. 5 . In  FIG. 3  to  FIG. 5 , the cooling unit  40  shown in  FIG. 2  is turned upside down. This means that  FIG. 3  to  FIG. 5  show the cooling unit  40  seen from below. 
     As shown in  FIG. 3 , the cooling blower  50 , the inlet duct  60 , and the cooling duct  70  that structure the cooling unit  40  are suspended from a lower surface of the floor panel  90 . Skeleton members  100 ,  101  for reinforcement of the floor panel  90  are fixed to the lower surface of the floor panel  90 , and the cooling blower  50  is fixed to one of the skeleton members  100 . The skeleton member  100  is firmly fixed to the lower surface of the floor panel  90 , and holds and fixes the cooling blower  50  so as to be able to cope with vibration and so on. Further, the inlet duct  60  is combined with an inlet port  51  of the cooling blower  50 , and the inlet duct  60  is able to lead air in the vehicle interior to the cooling blower  50  (see  FIG. 5 ). Meanwhile, a connection port  71  of the cooling duct  70  is fitted to a discharge port  52  of the cooling blower  50 , and cooling air discharged from the cooling blower  50  is lead to the battery pack  30  by the cooling duct  70 . 
     Water is prevented by a waterproof tray  80  from entering the cooling blower  50  from outside, and the waterproof tray  80  is also held by and fixed to the skeleton members  100 ,  101 . The waterproof tray  80  is structured from a resin, and provided with mounting holes  80 E at four corners of the waterproof tray  80  for fixing the waterproof tray  80  to the skeleton members  100 ,  101 . Further, the skeleton members  100 ,  101  are provided with mounting holes  100 E,  101 E, respectively, corresponding to positions of the mounting holes  80 E. 
     As shown in  FIG. 4 , the cooling blower  50  and the inlet duct  60  are fixed to the lower surface of the floor panel  90  to which the skeleton members  100 ,  101  are fixed. The skeleton member  100  is provided with two stud bolts  100 A for fixing the cooling blower  50 , and the lower surface of the floor panel  90  is also provided with one stud bolt  92 A for fixing the cooling blower  50 . Corresponding to the stud bolts  92 A,  100 A, the cooling blower  50  has mounting holes  50 A for fixing the cooling blower  50 , and is fixed to the stud bolts  92 A,  100 A by nuts A. 
     The lower surface of the floor panel  90  is provided with a bracket  95  having a clip fixing hole  94 B for fixing the inlet duct  60 . Corresponding to the clip fixing hole  94 B, the inlet duct  60  is provided with a mounting hole  64 B for fixing the inlet duct  60 , and the inlet duct  60  is fixed to the bracket  95  of the floor panel  90  by a clip B. 
     The floor panel  90  is structured from thin sheet metal in which a plurality of beads  91  extending in the vehicle-width direction are formed, and has a shape that covers the recessed portion  25   b.  The skeleton members  100 ,  101  fixed to the floor panel  90  are arranged on both ends of the floor panel  90  in a direction orthogonal to the beads  91 . 
     The skeleton member  100  is provided with mounting holes  100 D for mounting the skeleton member  100  onto the cross members  23  of the under body  20 . Meanwhile, the skeleton member  101  is also provided with mounting holes  101 D for mounting the skeleton member  101  on the cross members  23  of the under body  20 . The mounting holes  100 D,  101 D are arranged at positions corresponding to the mounting holes  93 D of the floor panel  90 . Therefore, the skeleton members  100 ,  101  are fixed to the cross members  23  together with the floor panel  90  by the bolts D (see  FIG. 2 ). 
     The skeleton members  100 ,  101  are made from metal plates having a given thickness. The skeleton members  100 ,  101  may also be formed by bending sheet metal. Since the skeleton members  100 ,  101  reinforce the floor panel  90 , the skeleton members  100 ,  101  are required to have desired rigidity. In particular, since the cooling blower  50  is fixed to the skeleton member  100 , the skeleton member  100  is required to have rigidity that withstands vibration of the cooling blower  50 . Thus, fixing positions, shapes, and materials for the skeleton members  100 ,  101  are set so that the skeleton members  100 ,  101  are rigid enough to reinforce the floor panel  90  and also withstand vibration of the cooling blower  50 . In this embodiment, the skeleton member  100 , on which the cooling blower  50  is mounted, has a wide shape. 
     As shown in  FIG. 4  and  FIG. 5 , the cooling blower  50  is a sirocco fan including the inlet port  51  that takes in air from a center part of a rotary fan (not shown) in a rotation axis direction, and a discharge port  52  that discharges air in a radial direction of the rotation axis. The cooling blower  50  is provided with three legs  53  having the mounting holes  50 A for mounting the cooling blower  50  onto the floor panel  90  and the skeleton member  100 . A power cable (not shown) is connected with the cooling blower  50 . 
     As shown in  FIG. 2  to  FIG. 7 , the inlet duct  60  is connected with the inlet port  51  of the cooling blower  50 . The inlet duct  60  is provided with an quadrangular inlet port  61  opening to the vehicle compartment  4 , a curved duct  62  continuous from the inlet port  61 , a connection port  63  connected with the inlet port  51  of the cooling blower  50 , and a cover member  65  that covers the inlet port  61 . The inlet duct  60  and the cooling blower  50  are fixed to each other by clips (not shown) in a state where the connection port  63  and the inlet port  51  are combined with each other. 
     A flange  64  is provided around the inlet port  61 , and the flange  64  is provided with a mounting hole  64 B (see  FIG. 4 ) for mounting the flange  64  onto the floor panel  90 , a mounting hole  64 C for mounting the flange  64  to the cross member  23 , and mounting holes  64 F for mounting the cover member  65 . 
     As shown in  FIG. 6  and  FIG. 7 , the open box-shaped cover member  65  corresponding to the quadrangular inlet port  61  is arranged above the inlet port  61 . The cover member  65  is provided with a top plate  65   a  that covers the inlet port  61 , a side plate  65   b  formed continuously from the periphery of the top plate  65   a , pairs of leg portions  65   c  extending downwardly from four corners of the top plate  65   a , respectively, a quadrilateral annular-shaped flange  65   d  that connects lower ends of the leg portions  65   c  with each other, and engaging pawls  65   f  projecting downwardly from a lower surface of the flange  65   d.    
     The top plate  65   a  is arranged above and separated from an opening end face H of the inlet port  61 . A lower end  65   b   1  of the side plate  65   b  extends below the opening end face H of the inlet port  61 , and covers the inlet port  61  so as to surround the periphery of the inlet port  61 . Therefore, there is an opening between the lower end  65   b   1  of the side plate  65   b  and the flange  65   d , thereby forming an opening communicating with the inlet port  61  between a side surface of the inlet port  61  and an inner surface (an inner wall) of the side plate  65   b . Then, an intake passage to the inlet port  61  has a passage structure that goes over the inlet port  61  once from below the lower end  65   b   1  of the side plate  65   b  and goes inside the inlet port  61 , and the structure of the intake passage to the inlet port  61  is a labyrinth structure. The labyrinth structure is a structure in which the intake passage to the inlet port  61  has a vertical zigzag configuration, and is a structure that restrains liquid from entering the inlet port  61 . 
     A sound absorbing member  66 , which absorbs operating noise of the cooling blower  50 , is provided on an inner side of the top plate  65   a . Noise is absorbed most when it is incident perpendicularly to the sound absorbing member  66 . Therefore, by providing the sound absorbing member  66  in a part facing the inlet port  61 , it is possible to optimize sound-absorbing efficiency. Also, a sound absorbing member  67  is provided on an inner side surface near the inlet port  61  of the inlet duct  60 . The sound absorbing members  66 ,  67  are structured from, for example, inorganic fiber such as glass wool, metallic fiber made of aluminum and so on, synthetic resin foam made from polyethylene resin and so on. 
     As shown in  FIG. 6 , the vehicle compartment floor panel  10  around the inlet port  61  is covered by a floor carpet  110 . The floor carpet  110  is provided with an opening corresponding to the inlet port  61 , and the floor carpet  110  includes two layers, namely, a surface layer  111  on the vehicle compartment  4  side, and a felt layer  112  that forms a back layer on the vehicle compartment floor panel  10  side. The floor carpet  110  is fixed to the vehicle compartment floor panel  10  by fixing means such as a clip. 
     As shown in  FIG. 7  and  FIG. 8 , the engaging pawls  65   f  have tapered tips and are formed from elastic members. The engaging pawls  65   f  are provided at positions in the flange  65   d  corresponding to the mounting holes  64 F of the flange  64 , respectively, and are engaged with the mounting holes  64 F. The positions where the engaging pawls  65   f  are engaged with the mounting holes  64 F are set to positions at which the felt layer  112  of the floor carpet  110  is crushed and compressed when the floor carpet  110  is sandwiched between the flange  64  and the flange  65   d . In other words, when the engaging pawls  65   f  are engaged with the mounting holes  64 F while crushing the felt layer  112  of the floor carpet  110 , the floor carpet  110  is sandwiched between the flange  64  and the flange  65   d  and fixed. Therefore, since the floor carpet  110  is crushed and sandwiched between the flange  64  and the flange  65   d  around the inlet port  61 , the periphery of the inlet port  61  is sealed. 
     Also, a dustproof filter  61   a  is mounted on the inlet port  61  in a detachable fashion for restraining foreign matters from entering the inlet port  61 , and the dustproof filter  61   a  is replaceable. Since the cover member  65  is able to be detached by using the engaging pawls  65   f , maintenance such as cleaning, and exchange of dustproof filter  61   a  are easily performed. 
     The cooling duct  70  is explained with reference to  FIG. 3 . As shown in  FIG. 3 , the cooling duct  70  is provided with the connection port  71  fitted to the discharge port  52  of the cooling blower  50 , a duct  72  widening towards a downstream continuously from the connection port  71 , and exhaust ports  73  that are duct ends discharging air to the battery pack  30 . 
     Next, assembling and mounting of the cooling unit  40  onto the under body  20  are explained. First of all, as shown in  FIG. 5 , the connection port  63  of the inlet duct  60  is combined with the inlet port  51  of the cooling blower  50 , and the cooling blower  50  and the inlet duct  60  are fixed to each other by clips (not shown). 
     Then, as shown in  FIG. 4 , the skeleton members  100 ,  101  are mounted and fixed to the lower surface of the floor panel  90  by bolts (not shown). The stud bolts  100 A of the skeleton member  100  and the stud bolt  92 A of the floor panel  90  are inserted through the mounting holes  50 A of the legs  53  of the cooling blower  50 , to which the inlet duct  60  is fixed, and are fastened by the nuts A. Thus, the cooling blower  50  is fixed to the skeleton member  100  and the floor panel  90 . By inserting the clip B through the mounting hole  64 B of the inlet duct  60  and mounting the clip B onto the clip fixing hole  94 B of the floor panel  90 , the flange  64  of the inlet duct  60  is fixed to the floor panel  90 . 
     Further, as shown in  FIG. 3 , the connection port  71  of the cooling duct  70  is fitted to the discharge port  52  of the cooling blower  50 . Further, clips (not shown) are inserted into the mounting holes  80 E of the waterproof tray  80  and the mounting holes  100 E,  101 E of the skeleton members  100 ,  101 , thereby mounting the waterproof tray  80  onto the skeleton members  100 ,  101 . In this way, the cooling unit  40  is assembled. 
     As shown in  FIG. 2 , the assembled cooling unit  40  is housed in the recessed portion  25   b  of the under body  20  in which the battery pack  30  is housed. Thereafter, a mounting position of the cooling unit  40  is adjusted, and then the cooling unit  40  is fixed by the bolts D. 
     After the cooling unit  40  is mounted, the floor panel  90  is covered by the floor carpet  110 , and the floor carpet  110  is fixed to the vehicle compartment floor panel  10  by fixing means such as a clip. Then, the engaging pawls  65   f  of the cover member  65  are engaged with the mounting holes  64 F of the flange  64  so that the floor carpet  110  is sandwiched between the flange  65   d  of the cover member  65  and the flange  64 . Due to the engagement, the floor carpet  110  is crushed by the flange  65   d  and the flange  64  and fixed. As the cover member  65  is mounted on the flange  64 , an upper part and periphery of the inlet port  61  are covered. 
     After the rest of the components (not shown) and the floor carpet  110  are mounted, and the cooling blower  50  is driven, air in the vehicle compartment  4  goes over the inlet port  61  once from below the lower end  65   b   1  of the side plate  65   b  and is sucked inside the inlet port  61  as shown by arrow G in  FIG. 6 , and discharged from the exhaust ports  73 . Air discharged from the exhaust ports  73  is blown to the battery pack  30 , cools the battery pack  30 , and then is discharged inside the under body  20 . 
     As stated so far, the lower end  65   b   1  of the side plate  65   b  extends below the opening end face H of the inlet port  61 , and covers the inlet port  61  so as to surround the periphery of the inlet port  61 . Therefore, the intake passage into the inlet duct  60  is a passage that goes over the inlet port  61  once from below the lower end  65   b   1  of the side plate  65   b  and goes into the inlet port  61 , and the structure of the intake passage is a labyrinth structure. Therefore, even though a large amount of liquid is spilled inside the vehicle compartment  4 , the liquid is restrained from entering from the inlet port  61  because an upper part of the inlet port  61  is covered by the cover member  65 . 
     Further, even though liquid flows around the inlet port  61 , the liquid is restrained from entering because the inlet port  61  is positioned above the floor carpet  110  and has a labyrinth structure. Therefore, the liquid is also restrained from entering into the cooling blower  50 , thereby reducing a malfunction of the cooling blower  50  caused by liquid. 
     Further, because of the labyrinth structure, a bar-like foreign matter is restrained from entering the inlet port  61 , thereby preventing damage of the dustproof filter  61   a . By restraining liquid from entering the inlet port  61 , liquid is also restrained from entering the cooling blower  50  even if, for example, the cooling blower  50  is arranged immediately below the inlet port  61 . The sound absorbing member  66  is provided in a part of the cover member  65 , which faces the inlet port  61 . This means that the sound absorbing member  66  is provided in a part with the best sound-absorbing efficiency. Therefore, it is possible to absorb noise of the cooling blower  50  effectively. 
     When exhaust pressure of the cooling blower  50  is high, there are instances where air with increased temperature after cooling the battery pack  30  moves around into the under body  20  and is flown out to the vicinity of the inlet port  61  from a gap between the inlet port  61  and the floor carpet  110 . When the air with increased temperature is sucked in from the inlet port  61 , efficiency of cooling the battery pack  30  can be deteriorated. 
     However, in the foregoing embodiment, since the floor carpet  110  in the periphery of the inlet port  61  is crushed and sandwiched between the flanges  64 ,  65   d , the periphery of the inlet port  61  is sealed, thereby improving seal performance. Thus, air with increased temperature is restrained from leaking out from the periphery of the inlet port  61 . Hence, air with increased temperature leaking out from the periphery is restrained from being sucked in from the inlet port  61 , thereby preventing deterioration of efficiency of cooling the battery pack  30 . Further, due to improvement of seal performance of the periphery of the inlet port  61 , it is possible to reduce leakage of noise from below the vehicle compartment floor panel  10 . Furthermore, even though there is a manufacturing error in the thickness of the floor carpet  110 , the manufacturing error is absorbed because the floor carpet  110  is sandwiched and compressed. 
     Since the cooling blower  50  is fixed to the lower surface of the floor panel  90 , the cooling blower  50  is in a state of being suspended from the floor panel  90 , namely, in a state of being arranged above the recessed portion  25   b . Therefore, even though under body  20  is inundated with water, it is possible to restrain water from inundating the cooling blower  50 . Further, since the cooling blower  50  is covered by the waterproof tray  80 , it is possible to further restrain inundation of the cooling blower  50 . 
     The cooling blower  50  is fixed directly to the skeleton member  100  having rigidity that withstands vibration of the cooling blower  50 . Therefore, even though the cooling blower  50  vibrates while the cooling blower is operating, the vibration is not transmitted easily to the floor panel  90 , the inlet duct  60 , and the cooling duct  70 , and it is thus possible to restrain noise caused by transmission of vibration of the cooling blower  50 . Further, since the skeleton member  100  is fixed to the under body  20 , rigidity of the skeleton member  100  is increased, thereby further restraining noise caused by transmission of vibration of the cooling blower  50 . 
     In this embodiment, since the floor panel  90  is reinforced by the skeleton members  100 ,  101 , the floor panel  90  has rigidity that does now allow the floor panel  90  to be deformed even if an occupant rides on it, and, as shown in  FIG. 1 , it is thus possible to arrange the cooling unit  40  in a part where ingresses and egresses of an occupant happens. Also, an influence of a load of ingresses and egresses on the cooling unit  40  is restrained. By providing the beads  91  in the floor panel  90 , it is possible to further improve rigidity of the floor panel  90 . 
     In the foregoing embodiment, there is an opening between the lower end  65   b   1  of the side plate  65   b  of the cover member  65  and the flange  65   d . However, the lower end  65   b   1  of the side plate  65   b  may extend until the flange  65   d  and the side plate  65   b  and the flange  65   d  may be integrated with each other. In this case, a plurality of slits are provided in the side plate  65   b , and air in the vehicle interior is sucked in from the slits, and then sucked into the inlet port  61  through a space between a side surface of the inlet port  61  and an inner surface of the side plate  65   b.    
     With such a structure, the leg portions  65   c  of the cover member  65  are no longer necessary, and the shape of the cover member  65  is simplified. Thus, foreign matters are restrained from entering the inlet port  61  even more. 
     In the foregoing embodiment, the engaging pawls  65   f  are used as structures for mounting the cover member  65  onto the flange  64 . Instead of the structures, fastening means such as stud bolts may be used. The case was explained in which the cooling unit  40  is arranged in an underfloor space of the floor panel  90 . However, even in a case where the cooling unit  40  is arranged under a seat, in a cargo room, and so on, it is still possible to apply the cover member  65  to the inlet port  61 . It is particularly effective when the inlet port  61  is exposed in the vehicle compartment  4  because the cover member  65  protects the inlet port  61 .